Thursday, December 31, 2009

Flied Lice

I learned to make fried rice when I was stationed in Japan. It generally comes out pretty good. Unfortunately, I've never seen a recipe that's exactly the same, although most are similar.

Old Rice is Best.

You want about two cups of COLD, cooked rice. Not sticky but properly cooked. I just wait for it to accumulate. When I have a couple of cups, I go ahead and use it in fried rice... then start accumulating rice for the next batch. (Does that make sense? Mebbe not. When cooking rice you generally cook a cup or two at a time but it's rare for you to EAT everything that you cook; there's usually a bit left over. So you save it. Then comes the day when you want to fix something to eat and see that you've accumulated a couple of cups of rice. So instead of cooking MORE rice you simply use the rice you have to make Fried Rice.)

You GOTTA have Green Onions.

Big flower pot. Buy some seeds or onion sets. Poke them into some sand or soil, keep it growing on a window sill or whatever. (If you've got the room, you can also grow your peas & carrots. Think SMALL. You're feeding yourself... and maybe one other. It's almost impossible to NOT find enough room to keep a few things growing. And a lot of things you don't even have to plant! Seriously! Buy a bag of Navy beans... those little white jobbies. Pour some in a jar. Add water. Let them soak for a while then put them under your sink. Rinse them out every day or two until they sprout. Then EAT THE DAMN THINGS! Call them a salad if you want. Or stir them into your Flied Lice... or simmer with a thin-slice of beef. (The thinner you slice it, the better.)

Snow peas... or whatever. About a cupful; mebbe less. If snow peas, you get to eat the pods as well as the peas. But experiment. If you've got a carrot, try chunking it up; mebbe some celery. Not too much. But not too too much. If you add carrot, remember that it will take LONGER to cook than anything else, so start it earlier.

MEAT.

Bacon works. Ditto for ham. In fact, ditto for damn near ANYTHING although pork is traditional. (Sausage is interesting.) No pork? Then think FISH, SHRIMP or CHICKEN.

(EDIT: We're not all the same. Thank God. Some of us eat pork but a lot of us don't. Take that sort of thing into account when cooking or inviting someone to share a meal... or a car-pool. It's not about Being Right or Being Wrong, it's about Being Human. We are different for a lot of different reasons and your job is to pay attention to the DIFFERENCES rather than the REASONS. If you've got a ship-mate who has different view of things dietary, respect them. The important part is accepting the differences rather than trying to change things. So there's your pard, working alongside in the same hangar. Except he goes around the corner four or five times a day to pray and you don't. Don't keep waving a cool one in his face -- he probably feels the same way about beer as he does about pork.)

The meat USUALLY takes the longest cooking time. Respect it. Low heat. You are RENDERING the meat. If it is too dry you'll have to add about one tablespoonful of oil.

You'll be cooking in a wok or fairly deep skillet. With the meat cooked, put it aside, increase the heat and stir-fry the vegetables. This should take only a minute or two -- big flame, LOTS of stirring. You know it's done when squeezing a pea causes it to pop out of its skin.

Okay, dump the veggies with the meat and add the RICE to the skillet. Not too much heat but lots of stirring; you're getting the rice HOT... but without causing the rice to turn into little plastic bits. So stir. And mebbe give it a sprinkle of water, if things look too dry.

EGG(s)

Two little brown ones, whisked up with some water. Or mebber one great big white one; same deal; whisk it up. Don't do anything with them right now EXCEPT to whisk them up; I'll tell you when to add them.

Now start putting everything BACK INTO THE PAN. Meat. Stir it in. ADD THE GREEN ONIONS (FINELY DICED). And the veggies. Stir & fold; everything is GETTING HOT. You can begin adding a little SOY SAUCE. The rice will have a characteristic CRACKLING sound. (No, NOT like that... kinda like steam or sizzling veggies.)

Got the EGGS? Okay, pour them all over the rice! Keep stirring. Briskly. You're just about done; you want everything to be FINISHED AT THE SAME TIME.

The egg holds things together... along with the bits of meat & veggies and rice and soy sauce...

It starts to SMELL like Fried Rice (which is what it is). Now you can fine-tune things to your particular taste, perhaps by adding more meat or more onion... or less. Or whatever! You are FEEDING YOURSELF. It isn't a contest, it is preparing something that TASTES GOOD and is good for you!

DIVVY UP THE SPOILS!

Fried Rice can be kept for a couple of days, assuming you don't let it lay about open. First, you divide it with whoever you're sharing. If there is anything left over you can decide if it's worth the trouble to save it. Packed in a plastic box, you can take it to work as a brown-bag type of lunch (nuke it for a minute).

Use your EYE to measure, as modified by your sense of smell and taste. Fried Rice takes only a few minutes to prepare so DON'T make a major production out of it.

I tend to view fried rice as a means of getting rid of left-overs. But that doesn't mean you can't start from scratch and build a meal around it. For example, you may prefer to have your fried rice with shrimp or even chunks of chicken; something to add a bit more horsepower to what would otherwise be rather plain fare. (Do you like frog's legs? I do! VERY good with fried rice.)

I like to add a lump of Chinese mustard to the plate, dobbing it up as an accent... or just to clear my sinuses :-) Some prefer to go all-vegetarian, serving the fried rice with fish, deep-fried egg-rolls or whatever.

One of the best compliments to fried rice -- in my opinion -- is crispy spare-ribs. This is definitely NOT a means of ridding yourself of left-overs but of preparing a real meal.

-R.S.Hoover
-31 December 2009

PS -- I'll try to add some snap-shots. But don't wait for them to appear; go ahead and give yourself a treat.

(EDIT. I think most American's call them 'chop-sticks.' I call them 'hashi' because that's what I was taught. Hashi are a couple of wooden sticks that you use to shovel food from it's container into your mouth. You hold the container right up against your mouth then get busy with your hashi shoveling the groceries down the hatch.

What you DRINK with your lunch is usually green tea. Or water. You don't use knives or forks but you MAY use a spoon if we're talking soup. Feeding yourself means getting the food INSIDE of you without making a mess. If you use hashi, it's pretty hard to make a mess. [Sip, slurp, shovel, shovel, shovel...] You don't need knives because you cut everything to bite-size during preparation.

The interesting thing about 'chop-sticks' is that you probably have some near you, no matter where you are. And if you don't, pick up some scrap spruce and MAKE a set. )

Monday, October 12, 2009

HVX MODS; How To Do It To it


Long, long ago, in a garage far, far away, a gaggle of VW mechanics gathered around a 1700 engine, which Volkswagen had brought out to replace the 1600. We were anxious to tear one down and see how you could improve on perfection. Actually, we were a kind of cheering section, giving the usual hi-fives and 'We're Numba Won!' as the autopsy progressed.

Right off the bat we got a winner when we pulled the valve covers to get at the rocker arms because the rocker-arm shafts were grooved for lubrication channels. That means a mod some of us had been running for nearly ten years had now been blessed with the Holy Crescent Wrench of acceptance in all factory-built VW engines (ie, this was in the early 1970's). Then came a minor scuffle over the thermostat; missing as they usually are on so many Volkswagen engines, with some of our band of experts admitting they'd never even seen one.

In the HVX MODS you need to cut eight rather accurate grooves in the existing rocker-arm shaft and things were heating up between the How-Toz who were automotive machinists with twenty years of grease under their fingernails and the Street People, which included the Shade Tree experts, arguing first, that the 1600 and earlier engines didn't need them because they'd run just fine until now, and the Do-It-Right Group which included some pretty good wrenches who had followed the HVX logic but were arguing how to cut the required groove. Those who were machinists were holding out for a shaped carbide cutting tool, whereas the Lo Buck Warriors with a teenie-weanie 7x10" lathe and a bench-top drill-press were insisting an angle-head grider with a 1/16" blade did the job just fine.

As usual, tasks ultimately descend to the abilities of the craftsman rather than the tools, with several examples of guys who built race-winning engines with a very modest inventory of tools. With jobs such as this the task often breaks down on how to hold the work... or how to hold the tools. In the photos you can see the rocker-arm shaft held in the three-jaw chuck of the lathe whilst the angle-head grinder is attached to the cross-feed by humungous rubber bands. Which is pretty smart. The grinder's speed is marginally controllable through the use of a 15A motor speed controller. This gives the machinist the ability to find a cutting speed that produces a clean, even cut without having the grinder try to climb the bar. The rubber bands provides the necessary amount of flex between the lathe and the grinder as each is brought up to speed, at which point the cross-feed is used to feed the tool -- the 3" dia. carbide disk spinning as fast as 18,000 rpm -- into the work, producing a groove of the required shape, depth and width. (Click on the picture). The builder, Mike Sample, has built a Double Eagle and has now turned his obvious talents to making himself an engine. Or rather, engines. Unsatisfied with the first, which I judged to be of about Porsche quality, he has turned his hand to a second which I'm guessing will be equal to something with entwined R's on the cowling.

Here's a shot of Mike's 'dirty' work surface - a section of marble counter-top. Next comes the grooving of the rockers and confirmation of their ability to flow oil through the Ford/Subie type adjusters. These swivel-foot adjusters date from the early 1960's when they were introduced by Ford of Germany. Additional pictures and some early HVX drawings will show how the lubricating oil wends its way from the oil pump, up the push rods, through the rocker arms and out of the adjustable rockers where it pools in the tops of the valve-spring retainers, to be thrown off, carrying with it a considerable quantity of heat whilest at the same time, reducing the wear of the rocker-arm shims. Off-road racers and hot-rodders have been using these mods since the mid-1960's but it came as a considerable surprise to find that many builders of Flying Volkswagens appeared to have never heard of them.

-R.S.Hoover

PS -- Some folks didn't like the look of the pix, worried that abrasives were getting into the lathe's guts & gearing. Personally, I've found that showing people what you set-up REALLY looks like generates more mail, asking if I've cut holes in a quilt and installed it over the tools.

Basic rule with abrasives is to catch them before they can get to surfaces that can be damaged by them. The usual method is to lay-out shop-towels, overlapping, giving each layer a spray of kerosene (then) or WD40 (now) . By the time you get done, the shop has vanished from your How-To pix, leaving you with pix that look like you've set-up atop your bed. While these pix may not display reality, they have the advantage of showing the newbie how the parts are mounted in the tool and what tool(s) you are using.

Nowadays, with the ready availability of tempered aluminum and small lathes that are accurate and affordable, it's as though our shops have shrunk. Covering it up with shop towels gives an even worse impression, in my opinion. - rsh

Thursday, September 24, 2009


Have you seen this? Smaller than even the smallest of the lap-tops, it's usually referred to as a notebook computer. This is the 'Aspire One' and it's made by Acer. This particular model costs about $400, thanks to its larger hard drive -- 141 GB -- and a high capacity battery. The usual price is about a hundred dollars less. It has an Ethernet port -- the one that looks like a big telephone jack -- three USB ports, an SD port for memory sticks and an outlet for a high-density video monitor. Plug in a DVD drive, an auxiliary keyboard and a flat-screen display, it will make a fair-to-middlen' desk-top. Wireless is built-in, as is a high definition camera, making it a handy-sized package for people who may need to do some computing on the go.

The Aspire One weighs two pounds fourteen ounces with the battery pack accounting for about twelve ounces of that. Acer does not provide a carrying case but there are a number of them available from the size of a back-packs to a simple envelope made of wet-suit material costing about ten bucks. Compared to a regular lap-top such as the eight and a half pound HP Pavilion shown below, the Aspire One is a dwarf.


The little Acer allows me to convert otherwise wasted time into something useful, thanks to DeltaCAD and AbiWord. I've already told you about DeltaCAD so allow me to introduce you to AbiWord, a free word processor that actually works. The Acer comes with some Microsoft software but it turns out to be teaser-ware, since it turns itself off unless you cough up some dough at some future date. Having no faith at all in Billy and his merry band of hapless programmers, even before I bought the Acer I started looking for something to use instead of the Microsoft software. Seriously, for writing I'm still running Word Perfect on my other computers. I was willing (and able) to pay for decent software but almost everything I tried appeared to have been written by children or failed to pass my quest for practicality. Which made AbiWord a delightful surprise. Not only is it well written, it's free, with no strings attached... so far.

Having cancer means spending a lot of time in doctor's offices. Not only does that mean a lot of time traveling too and fro, once you've arrived (always fifteen minutes early, as requested) you'll find that physicians have a bit of trouble reading a clock. I've never been an especially patient person and find I'm even less so now that I've been diagnosed with cancer. I find it rather ironic that the people who are trying to prolong my life appear unconcerned with chopping great chunks out of it.

-R.S.Hoover
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10/09/2009

Pull up the other comments you will see that Joseph and others have already caught my spelling error. Truth is, it's a sprawly kind of house, the Acer was in the bedroom and I wasn't. 'nuff said.

I received several private messages. I assume they took the trouble because they wanted it to be private so let's keep it that way. But on the whole, most of the private posts were about prices, present or about to become public which had me scratching my head because I'd already bought the thing. Ditto for some pricing info on chip, SD sticks and so forth. Couple of hacks . But the really BIG SURPRISE was in not receiving any. Usually, you buy something with a CPU inside you can count on several messages about how to make it do tricks. This time was nada. I'll let you figure out what that means.

Overall, the palm-top has proven to be well worth the price. No sense in me telling you why it's useful... sorta like trying to sell computers in the '70's. If the customer doesn't already have an application that needs to be computerized then you can't sell them one to do their taxes or whatever... computers define their own applications, not the other way around. Mostly, I like it; it has proved handier than I thought.
-R.S.Hoover

Tuesday, August 25, 2009

Good Salad

GOOD SALAD.

1/2 head of Iceberg lettuce
2ea Medium tomatoes
1 'ring' from a Bermuda onion
1/4lb smoked salmon
1 heaping tablespoon Mayonnaise
1 Bud of Garlic

GARLIC
Peel the bud of garlic, smash it with the flat of your knife and rub the crushed garlic bud all over the bowl in which the salad will be mixed.

LETTUCE
You want it crispy. The best way to ensure that is to punch out the stem, rinse the head with clean, cold water, then bag it and leave it in the refrigerator overnight. When you take it out of the reefer it will nice and cold. Poke your thumbs into the hole where the stem used to be, tear the head of lettuce in two then tear one of the halves into bite-sized chunks and toss them into one of those centrifugal spinner jobbies and pump it up & down for about a minute. This will fling off most of the water. Toss it into the bowl. If lettuce is not available you may use a couple of six-inch cucumbers, well chilled then peeled and diced.

TOMATOES
To me, a medium tomato is about 2-1/2 inches in diameter. Stand the tomato stem-side down and quarter it. Slide it apart so as to leave two halves and slice them three times so as to leave four chunks. Do this for both tomatoes, tossing the chunks into the salad bowl.

ONION
You may use green onions here if you wish. Indeed, depending on the season and your location, green onion may be all that is available. In either case, dice the onion so as to produce chunks no larger than the chunks of tomato and toss them into the bowl.

SMOKED SALMON
Shred the salmon with a fork. If salmon isn't available almost any other smoked fish will do: Smoked Tuna, Albacore, etc. If you are at or near a seaport you are bound to find someone selling smoked fish. Try a chunk of whatever is available. When you find something you like, use it in your salad. If you are out in the boondocks, try a can of smoked sardines or mackerel.

When available, you may substitute avocado for the fish.

Add 1 large tablespoonful of Mayonnaise then season to taste using the juice of two small limes or half of a lemon. Be wary of adding salt if you've used smoked fish, which is often already salted.

Serve with cold beer and crackers or bread. In the photo you can see a dish of wholewheat bagel that I've toasted to make it crunchy then sliced into four pieces.

The salad is meant to comprise the whole meal but it may also be served with steak, barbecued ribs, roast chicken and so forth.

-R.S.Hoover

Saturday, August 8, 2009

Traditional Sized

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I am a ham radio operator, the holder of a General License although I have retained my original Novice license. I did that so as not to intimidate the youngsters who attended my classes in Morse Code and basic electronics.

Many were drawn to ham radio because it allowed them to maintain communications with their home or office... assuming there was another licensed ham radio operator on the other end. But ham radio was also of benefit during the Voyager's around the world flight in 1987, when a group of us monitored the progress of the flight.

I still use ham radio to monitor the location of my 1965 VW bus. Should I ever go missing in the desert -- or should the bus be stolen -- its location can be determined to within 50 meters or so through a combination of ham radio and GPS.

In the delightful novels of Alexander McCall Smith, author of 'The No. 1 Ladies Detective Agency' and more than thirty others, Mma Ramotswe, the Botswana detective describes herself as a lady of 'traditional' size. By comparison, the 'traditional size' of the station of the typical ham radio operator would fill six to eight feet of shelf space, which makes it rather difficult to grasp the size of the present-day 'communications station,' which fits in my ear.

Actually, the ear-piece is just the microphone and head-phones. The transciever is my cell phone, which fits in my pocket. Anyone having the number of my cell phone may contact me any time I am 'on line.' Which isn't very often.

Of course, the modern-day system of cell phones depends upon the existing system of land-lines to work. That is, our cell phones connect to a local receiver-computer which locates the station you are calling. It then uses the land-lines to send your message to a transmitter/receiver nearest to the station you are trying to contact, which then connects you to that station. The key point here is that your cell phone depends upon the existence of the traditional web of wires or cables. Should there be a disaster that damages those land-lines, your cell-phone will not work, whereas the traditional ham radio station will continue to work since it does not depend on land-lines.

Today I am measuring valve springs for four heads. I'll be working in the shop where I can't hear the ring of a telephone. So I'm wearing my cell phone in my ear. The ear-piece talks to the cell phone in my pocket. About the size of a pack of king-size cigarettes, this has become the 'traditional size' for personal communications

-R.S.Hoover

Sunday, July 26, 2009

IT'S ALL ABOUT HEADS. HONEST!

I've been trying to explain the importance of your cylinder heads. The subject is fairly complex and I've found the explanation difficult, having to stop and start over each time I came to a point that I assumed was common knowledge. Along the way a couple of my Mystery Followers checked in
. I didn't know if there was a secret handshake or password or some other Googleistic requirement. There wasn't. The 'Followers' were just guys who wanted to know each time I posted something to the blog. Fair enough, except for the fact I have been virtually unable to post anything anywhere for the past couple of weeks.

It's called neuropathy.

I get a basic blood test every week and a complete work-up every month. The doctors use the information from the blood tests to tailor my cancer treatment, altering my medications as needed to keep the tumor in check. With multiple myeloma the tumor isn't a single mass at one site, but distributed inside my bones at a number of sites. Which means they can't go in and cut it out. But the right combination of medications can limit its activity, keeping me alive a little longer. Unfortunately, some of the medications trigger side-effects, such as making your fingers 'tingle' to the point where you can't do much with your hands. And that includes TYPING.

So the answer to the several messages wondering about my lack of activity on the blog is 'neuropathy.' Which is the medical term for having your fingers tingle. Especially when they 'tingle' so badly as to prevent using your hands for a lot of things. In my case, one of the things I couldn't do very well was typing.

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As for it being all about heads, it really is -- so long as we are talking about Volkswagens. And since it's about heads, it is also about the various TOOLS needed to work on your heads, such as a tool to compress the valve springs so you can remove your valves. You also need a tool to measure the strength of your valve springs when they are compressed to a standard height. Then there is the need for tools to cc your combustion chambers. And a tool to measure the amount of play in your valve guides.

A lot of the articles I've written have been to show you how you can MAKE those tools, saving yourself hundreds of dollars.

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As of last Wednesday I've been taking a medication that is different from the one that triggered the neuropathy ( nerve pain ). My fingers still tingle a little bit but nothing like before, when it got so bad I couldn't type. If my scores on this weeks blood tests show the new medication to be as effective as the old, then the problem will hopefully go away and I can get back to explaining what has to be done to a set of heads and why. So... fingers crossed.

-R.S.Hoover

Saturday, July 11, 2009

The Fearless Leader Report

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Yes, it is I; your Fearless Leader. I've still no idea what my duties entail but I see the number of 'Followers' has increased.

You guys are really making me nervous. I appreciate the implied compliment but I assume it's some kind of inside joke. No, I don't expect you to run away, it's just that I don't know what I'm supposed supposed to DO.

So until the other shoe drops, I'll keep doing what I've been doing. Which is not much, if the past week is an example.

According to my blood tests the tumor remains in its cave. I am trying to regain my lost weight and restore my physical strength but I'll tell you pard, this is one hell of a chore. Some of the drugs needed to keep the tumor in its quiescent state also act to suppress my appetite -- a neat example of Catch-22. With my toothpick arms and spindly legs just standing up is a test of my strength. To stand up AND work at the same time is a real test of will. What happens is that after working for a few minutes I experience spasms in my lower back, forcing me to sit down. After sitting for a time the pain goes away and I'm able to repeat the procedure.

About the only people who see something good in all this is our three 'outdoor' cats. (We also have one 'indoor' cat.) Whenever I sit down I acquire a lapful of cats.

Yes, even when I'm writing something like this... it's a warm evening so I left one of the kitchen doors open. I've no idea how cats know when a lap appears. Perhaps laps give off a scent... or make some characteristic sound. Whatever the means, it is quite effective. I've got the proof right in front of me :-)

-R.S.Hoover

Monday, July 6, 2009

Valve-job Tool





The Volkswagen engine uses poppet valves, as do all other cars today. The exhaust valves are the weak link in any engine but especially so in air-cooled engines, be it Pratt-Whitney or Volkswagen. If we want to keep tabs on our engine's condition all we need do is keep track of the condition of our exhaust valves since they are the first part to fail. Of course, we never allow them to fail, we merely keep track of their condition and when they tell us they are about to fail, we pull the heads and give them a 'valve job.'

To keep track of them we use the leak-down test, pulling the heads any time the leak-down is more than twenty percent or thereabouts. To do a 'valve job' means to remove the valves and restore the worn parts to spec. In about eighty percent of all cases, the worn part is the valve itself but other parts associated with the valve – the valve guide, the valve seat or the rocker arm – may also require repair or replacement. Since replacing the valves is the most frequent chore, that's what I'll talk about here, with a minor mention of the other valve-related components as we come to them.

The valve is opened by the cam but it is closed by the valve spring, which we must compress in order to remove the valve. The valve spring is held in place by a retainer and a pair of valve keepers. That is, the retainer fits down over the stem of the valve and rests on the valve spring. The stem of the valve has a pair of grooves into which the valve keepers fit. When so fitted, the valve keepers lock into the grooves and wedge into a tapered bore in the retainer, which sits on top of the valve spring. So long as the spring is in its proper position and is not damaged, the valve will not come loose, even though it may be actuated several times per second.

The valve spring is a coil-type compression spring that is progressively wound; the turns nearest the head having a higher ratio of turns per inch. This allows for easier opening. But like all springs, the Volkswagen's valve springs are effected by heat and age. VW valve springs typically take several million actuations before showing any sign of weakening. In a vehicle, the stock VW engine needs a valve job after about thirty thousand miles of service but Flying Volkswagens are rarely of stock displacement (which is less than 100 cid). Flying Volkswagens may be as large as 140 cid and their valve wear is a function of the work they do, which may be several times that of a vehicular engine. These non-stock 'Big-Bore Strokers' may need a valve job as frequently as every ten hours... or as infrequently as every two hundred hours, depending on how the engine is used.

The Volkswagen is a robust little engine that, like all Otto Cycle engines, provides a wealth of precursors of impending failure. So long as the engine is properly assembled and operated within its limitations by a pilot who has learned to recognize those clues, it is as reliable as any other engine in its class. But this puts a heavy burden on the pilot, who must be able to recognize those clues.

In an airplane the condition of the valves is determined by a leak-down test, which is performed periodically, the length of that period determined by the manner in which the engine is used. The leak-down tests (ie, wet & dry) reflects the amount of wear of the valves and rings, with the valves wearing at a much faster rate than the rings.

To perform a valve job we must remove the heads from the engine and the valves from the heads. Exhaust valves are replaced rather than reground but the intake valves may be reground and re-used.

When doing a valve job we check the valve springs against the spec in the work-shop manual. The diameter of the valve dictates the amount of spring tension needed to achieve proper closure. In specifying one valve tension but with a very wide tolerance for both the intake and the exhaust, you are seeing one of the many compromises Volkswagen made to keep down the price. For example, when the spring pressure is given as 96 lbs (+/- 6lbs) it is fair to assume that the smaller figure ( ie, 90 lbs) should be used for the exhaust and the larger figure (ie, 102 lbs) is used for the intake valves.

One of the more interesting features of the Volkswagen engine is that each lobe of the cam actuates TWO valves rather than one. That is, the intake valve of the #2 cylinder is actuated by the same cam lobe that actuates the intake valve of the #4 cylinder. The action of the cast iron cam as it wipes across the face of the cast-iron cam-followers (ie, the 'tappets') is the engine's major source of metallic residue, which in turn is the main source of wear in the engine's bearings and oil pump. To minimize this wear the wear-factor of the cam must be exactly twice that of the cam followers. The pressure of the valve spring plays a critical role in the wear-factor of the valve train as a whole.

At this point you need to go to http://home.hiwaay.net/~langford/

That's the home page of Mark Langford, who has contributed about three Ph.D's worth of information to the pool of knowledge all of us are swimming in. Specifically, I want you to read about how Mark measured his valve springs. Here in the Blog I've posted an article about a tool I made for that purpose but I was dealing with forty or fifty springs at a time. Like Mark, you are building only one engine. His method is more practical than mine.

What I want you to do is to COPY the method Mark has used for measuring his valve springs.

The assumption here is that you have only EIGHT valve springs. What you'll want to do is create the best possible match from BANK to BANK.

If you are running stock heads... meaning you are using valves of stock diameter, the spec for your valve springs is 126, +/-9 at a compressed height of 1.32". Which may be translated as 117 for your intakes and 135 for your exhaust.


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Doing a leak-down test, the 'wiggle' test and doing a valve job are common chores for those of us who flys behind a Volkswagen engine. Given that my life literally depends on the quality of the work done to my engine, it should come as no surprise that I'm unwilling to trust any work done by a mechanic who is NOT certified by some agency or authority equally concerned with the quality of his craftsmanship. Since there is no such agency for auto engines converted for flight it seems logical that I do such maintenance myself. There are a few tools specific to these tasks. They are available from most of the larger after-market retailers who specialize in VW parts. But it is the nature of the Volkswagen philosophy that the tools may also be fabricated by the individual mechanics. Volkswagen used to provide a booklet of dimensioned drawings for such tools but no longer does so.

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The first illustration in this article shows the two most recent types of valve spring retainer used on Volkswagen engines. As you can see, we need to provide for a retainer approximately 1-1/4" in diameter. Once the tool makes secure contact with the retainer we need to provide a downward force to compress the spring. It doesn't take much -- about half an inch will do. We then use a scribe or other pointed tool -- a sharpened nail will work -- to free the keepers from the grooves in the stem of the valve. Once the keepers are freed, they are removed but kept sorted according to the valve from which they came. A magnetized scriber works best or you can use a magnetic pencil.

For those of you without a metal lathe, making a tool that fits over the valve retainer is the most difficult part of the job but as you can see from the photos there are any number of workable options. And those rivets you see started out as regular nails. Just cut them off short.

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As a point of interest the Single Port (SP) head shown in the photos is a junker. The spark plugs were installed WITHOUT anti-seize compound, a necessity with regular spark plugs and ALUMINUM heads. Both of the spark plug holes have been stripped until they are almost smooth.

The shade-tree fix for a stripped spark plug hole is to install a Heli-Coil (a brand name), which is coil made of wire having a diamond-shaped cross-section. The inner diameter of the coil matches that of the spark plug whilst the outer diameter matches that of a special tap that is sold with the Heli-coils as a kit. The Heli-Coil tap is threaded into the hole WITHOUT drilling it to a larger size.

There is another type of spark plug repair kit which uses a metal sleeve having it's ID threaded for the spark plug and it's external thread of some larger diameter, usually that of a regular size. This type of repair requires the spark plug hole to be opened up to a larger size, usually with a drill. To use this type of repair kit on a Volkswagen engine that is still in the vehicle the mechanic needs to use an angle-head drill-motor or a reamer, since there isn't enough room to use a regular drill-motor. (Clearly, this does not apply to aircraft installations.)

Unfortunately, the point over looked by shade-tree mechanics is that ANY form of spark plug hole repair that involves the use of a coil or sleeve must not be used on an AIR-COOLED engine (!!) The sleeve or coil upsets the resistance -- both thermal and electrical -- of the spark plug.

The fact this type of repair is allowed on WATER-COOLED engines fitted with aluminum heads is taken by non-professional mechanics to mean the procedure may be used on ANY engine. Sadly, this is not true.

So how DO you repair a stripped spark plug hole? Working from the chamber-side of the spark plug hole you hog out a crater of generous proportions, pre-heat the head to about four hundred degrees and go at it with TIG ( or even MIG, if you've got the right equipment) ...and fill the crater with molten aluminum. The head is then put back into the oven, the oven is shut off, and the head(s) are allowed to cool to room temperature.

(Did you notice the implied plural? The plural does not refer to the fact VW engines have two heads but to the fact it is not economically practical to repair damaged heads one at a time. What you do is wait until you have about two dozen damaged heads then tool up to do them all at once.

But here in Southern California, with more than twenty-one MILLION registered vehicles(*) -- and more air-cooled Volkswagens than anywhere else in the country, there was another option.

During that period (circa 1970's) for small shops such as mine, it was worth while to find a bigger shop that regularly overhauled heads on an assembly-line basis in batches as large as 250. They would allow small shops to add their heads to the batch, inspecting them to ensure all of the preliminary work had been done, and done to their specs. They would then do ONLY the welding, charging a nominal fee.

The point here is that the proper repair of a VW head with a stripped spark plug hole is to weld it up and re-machine it. For someone FLYING behind a Volkswagen engine, if it suffers a stripped spark plug hole your best option is to replace the head, since the repair would cost more than a replacement head. But don't forget that any replacement must be an EXACT match for the old head, meaning identical chamber volume and valve train geometry.

And this time remember to apply a dab of anti-seize compound to the first few threads... and then wipe it off. The tiny amount that will remain deep in the threads is all you need.

A handy way to prevent cross-threading a spark plug is to install it full-depth using only your fingers. It will then take little more than one turn to achieve the required torque-spec (22 ft/lb). And be sure that's done with a NEW WASHER. (They've got them at the real automotive parts places; don't waste your time in those chain-store auto parts retailers.)

Finally, I recently read a post where a fellow stripped his heads because his spark plugs projected into the combustion chamber. This would NEVER happen on a properly assembled engine, where checking the projection of the plug is a standard step during pre-assembly.

If the proper plug projects too far you will want to add a solid copper washer between the regular washer and the body of the spark plug. That is, you want your new, crushable washer to be in contact with the head on at least one side. Spark plug manufacturers provide solid copper washers as well as new, crushable washers. They're usually racked in the 'Dorman's' trays (those orange & black trays taking up wall space in the back of the store) :-)

---------------------------------------------------


(to be continued)

Thursday, July 2, 2009

Designing a Bigger Box

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There I am in the patio, holding steady at 151 pounds. Or 10.8 stone if you hail from across the pond. Or 68.5 kilos. Down a tad from about 235 pounds back before cancer came to call.

My height has also shrunk, apparently due to the destruction of my 3rd lumbar vertebrae; enough so that my height is now 70-1/4" instead of 72", which explains why my trousers are not only too loose but too long. Here again, the cause is due to the tumor munching away on my spine. In fact, even my feet have gotten smaller. Not in length but in most other dimensions. Which means my feet sort of rattle around in my shoes... now that the edema-like swelling is no longer a problem. (For several months the edema forced me to wear an old pair of Uggs that I'd modified with a razor, turning them into enormous slippers.) As a point of interest, the edema was a side-effect of the medication. As I became accustomed to the medication, the edema slowly went away.

Early in the history of this blog is an article about an apprentice's tool box, which was one of those tricky bits used to teach people how to rivet. A number of you, including at least one shop class, have found the tool box of sufficient interest to tackle it as a project. But more than one of you has pointed out that the dimensions of the box, while practical for tools of the 1930's, is a bit too small for tools of the 21s century. Which I pretty much ignored. After all, the project was meant to teach people how to rivet; it's functionality as a box for carrying tools was not its purpose. But when this point was raised by a third person I figured it was time to take another look at it. You can pretend that's what I'm doing in the photo above :-) (I think my wife took the snap shot to show my sister how skinny I've become.)

So I will go ahead and post a set of drawings for a bigger box; something more suitable for a modern-day kit of tools. Personally, I have not yet found the need for such a thing but judging from my mail, several of you have.

-R.S.Hoover

Monday, June 29, 2009

The Crooked Foundation


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During my last years in the Navy I was involved in what was known as the Technology Transfer Program. The idea was to pass along modern technology to friendly nations; to try and bring them up to speed in using modern-day communications and computers. I often wondered why. We were fresh out of Russians, pounding their shoe on the table at the UN, shouting they would bury us. 'Rebels' were occasionally given a polite mention.

The quotes are because it was often difficult to tell who was a rebel and who was not.

The program was a marvelous success, of course. (Have you ever heard of a government program that was not?) In fact, most of the programs were dismal failures, for reasons that were painfully evident. For example, we were tasked with teaching the operation and repair of solid-state devices to electronics technicians who had never been exposed to solid-state devices. They tried -- and there were a few who did pretty well -- we'd been given the best people they had... and 'best' was determined by how well they did with tube-type equipment, the newest being Vietnam-era junk, long since replaced by more modern equipment.

A lot of the mail I get reminds me of those 'Technology Transfer' programs. And for the same reason. For example, a message arrives from a fellow who claims to be qualified in all the basic stuff needed to maintain a VW engine, having owned his bug or bus for a number of years. In the message he provides a number of symptoms that make it clear the problem is worn valve guides, with a probability close to 100%, plus the fact that replacing the valve guides is a fairly common chore for the Volkswagen engine due to the small diameter of the valve stems and the fact air-cooled engines operate at a significantly higher temperature than their water-cooled cousins. Fortunately Volkswagen kept those things in mind when it designed the VW engine so that replacing the valve guides, which you'll need to do about every third valve job, is a straight-forward procedure, needed only a couple of additional tools.

With those things in mind I pointed the fellow toward the valve guide procedure, which I believe is fairly complete.

Unfortunately, the fellow had never done a valve job. And of course, he didn't have even the most most basic tool, the valve spring compressor, needed to dismantle the heads. His definition of Major Maintenance was replacing his clutch disk.

In the end, he bought a pair of 'rebuilt' heads from a the local 'expert' and took the first steps down the slippery slope that eventually lead to him getting rid of his Volkswagen.

Ditto for Flying Volkswagens, except that first step is liable to happen within a matter of hours rather than years. Why? Because a flying Volkswagen is liable to be operated for hours at a time at a level of output rarely seen in a bug or bus. The tricky bit here is the belief that all rpm's are the same; that running 3600 rpm in a plane will be the same as running 3600 rpm in a car. It isn't... unless the manifold pressure happens to be the same as well. The bottom line is that you can literally wear out a VW engine in a matter of hours.

Which isn't especially bad, assuming you understand what you are doing and keep a spare set of heads on hand.

-----------------------------------------------------------------------------

I'm a bit more circumspect nowadays, with people having assembled an engine from a kit of parts. Do you have a valve spring compressor? A rack to hold the removed valves? Do you have these foundation tools? Because if you don't, you'd better get them. You can buy them or make them but you absolutely can not do without them. These tools are the foundation of engine maintenace and to do without them is to build on a crooked foundation; things simply can not come out true.

This article shows a fixture for holding valves. These happen to be made of wood but you can make them from cardboard, assembled with duct tape, or scrap aluminum if you'd like a simple riveting project. But I like to work with wood and had some scrap handy....

Thursday, June 18, 2009

CANCEROUS VOLKSWAGENS

This is a red 'loaf, I think a '71. No engine installed but it's on its own wheels. Used for storage so some stuff has to come out before it can go. There might be a Type IV stored in it -- I haven't been into it in more than a year.










There is a small propane tank for this one. Lotsa junk inside.


This is the one down in the field. No running gear but trick upholstery. Loaded with junk. Needs to be skidded onto a flat-bed... after removing the vehicles in front of it.




That's Grendle. I patched her floor & door jams, did some work to the nose & cockpit (floor was rusted out). Front axle is removed for overhaul... which never happened. Ditto for engine, except it was a swap; the core engine is still here, plus the tranny & aft running gear. The running gear could be re-installed in a couple of days but it's a long way from running -- needs a fuel tank & plumbing, for example, plus I haven't finished the doors.


There is a nose clip down in the field which was for this vehicle but now it's a case of winner take all. There's a shot of her nose.

Wednesday, June 17, 2009

HVX_MODS WARNING !

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TO ALL:

In doing the HVX mods you must drill two holes which result in the connection of the right-side tappet oil gallery to the #3 cam bearing.

THIS DRILLING IS CRITICAL!

On some engines there is not enough metal to allow the two new holes to connect without breaking through to the outside of the crankcase. THIS WILL DESTROY THE CRANKCASE.

Before doing the drilling you must make sure there is enough metal. A warning to that effect has been on the drawings since they were first uploaded but in some cases it is difficult to take an accurate measurement, in others the builder lacks the proper tools.

-R.S.Hoover

Saturday, June 13, 2009

What's the Secret?

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In addition to the Comments attached to to the tail-end of every Blog entry, a lot of folks contact me directly via email ( veeduber@chuggers.net ) In response to my last Blog entry ('Good News!' ) I received several email messages. One of them sounded a bit forlorn... and failed to provide a valid email address, making it impossible to answer them directly. What they wanted to know was the 'secret' of receiving good medical care.

I don't think there is a secret. But I think a lot of people have failed to understand the realities of modern medical treatment and a good way to prove that is to take a look at medical treatment in the past. You know the ones I mean.... where the Hero gets sick and ends up in the hospital attended to by the modern-day version of Florence Nightingale, where the All-Knowing physician apparently lived in a room just down the hall. The Hero's medical record -- magically reduced to a single sheet of paper attached to a clip-board hanging on the foot of the bed -- contained everything doctor might want to know.

You can get a good laugh out of some present-day hospitals, the ones where the nurses don't even speak English and the physician might only come around one day per week. My case will give you a nice example of modern-day medical treatment, where the patient becomes their own hospital.

As most of you know, I have Multiple Myeloma, a form of blood cancer for which there is no cure, although it can be treated. The fellow who wrote me is apparently dealing with medical problems of his own, wondering what's the secret to getting a bit of good news.

Although I don't believe there is any secret, the difference between my treatment and his could very well be the quality of the hospital he uses, which is a play upon words since, as I've said above, in the modern day we often become our own hospital.

See that clip-board hanging on the foot of the patient's bed? Back in the Good Ol' Days... whenever that was, that was the patient's 'Vitals Chart' and listed the patient's pulse-rate and temperature, recorded however often the doctor requested it, with every four hours being typical. Nowadays your vitals usually present more data, such as blood pressure and the oxygen content of your blood. Being my own hospital, I collect & record my own vitals, generally using modern electronic instruments. As a pilot I already had a Nonin (brand name) blood-oxygen instrument, and the electronic thermometer seemed to arrive along with the kids. But I had to buy an electronic blood pressure device (less than $20).

I usually take my vitals every day. The data is recorded in a notebook and again into a computer file. The notebook makes the data portable, allowing the physician to see it, should they ask. But most doctor's offices prefer to record your vitals themselves.

I also record my weight, usually after my shower.

My pills follow a four-times-per-day schedule. There is a listing that shows what medications I take, how much, and when they are taken. There is also an 'Origination List' showing which physician prescribed which pills, what they are for and when they were prescribed. Making sure this list up to date is a basic chore each time we visit any of the five doctors. Since my ailment is being treated by a team of physicians, it's up to me to ensure that all are made aware of any change to my mediations, especially when there is the possibility of any drug interaction.

Many cancer patients say the cure is often worse than the disease. I've got a hunch they need to spend more time talking to their physician because a slight change in dosage or frequency can eliminate many of the side-effects which give rise to such claims. (In my case there isn't any cure, but that doesn't mean it has to be fatal.) Working with the physicians over the past year has resulted in a nice balance of medications which has reduced the side-effects to little more than a nuisance. That doesn't mean a full recovery -- the tumor has caused too much damage for that. But neither does it have me puttering about in a wheel chair. In either case, each of us is the master of our fate. For someone to feel that good medical care involves some secret is more likely to cause others to doubt the person's perceptions than the quality of their physician. On the other hand, over the last few years there has been enormous strides in medicine and some physicians have failed to keep pace. If the cure is indeed so terrible it would seem logical to seek a second opinion.

Personally, if there is any secret it probably has to do with the cooperation between the physicians and the patients, with the patient playing the major cooperative role. Physicians simply have too many depands upon their time. From the outset of my treatment Dr. Bessudo, my oncologist, insisted upon a team approach, calling upon other physicians as needed. He also said that I would be a part of the team but I didn't realize what that role entailed. Looking back on the past year it is now obvious that much of my progress was due entirely to the roles played by my wife and myself. While that may sound self-serving I can swear it is not.

In effect, my hospital covers about 200 square miles (!). In the past year my wife has never failed to deliver me to the proper physician, on time and suitably attired. (Indeed, she uses a check-off list to ensure I have wallet, cell-phone and so forth -- ten items, all tolled.) Nor has she failed to procure my medications, and to dole them out in the proper frequency, from once a day to once per week. I suspect support of this nature is not considered much of a secret when in fact it forms the very foundation of my treatment.

A recommended change to my medication appears automatically on the other physician's computers, supported by an often cryptic email. Often times a recommended change will produce a flurry of emails before the matter is resolved, often based on economic factors. (You won't believe what some drugs cost!) New drugs come on the market every day and if your ailment matches the intended purpose of the drug you're liable to be used as something of a lab-rat. Before trying something new, if you are being treated by more than one physician, it's a good idea to make sure they are all aware of the new drug and any possible side effects. This kind of information is available in the Physician's Desk Reference (PDR) and from the company offering the new drug. The key point here is that you... YOU need to devote some time to your treatment. As I've said, physicians are busy people. Your treatment must be a cooperative effort.

Baffled by all those medical terms? Then write them down. Now go look them up on your computer. Learn how to pronounce them properly. Write down any questions you may have. Rehearse your visit to the doctor. Be concise! Don't waste her time. (Nor his.)

Are these things secrets? I don't think so. Indeed, I've a hunch your physician will appreciate your enlightened interest.

-R.S.Hoover

Tuesday, June 9, 2009

Great Day!

Just back from the Doctor Shop. This was the internist, Dr. Kipper. Turns out, he has not been getting copies of my blood-work from the lab. (The lab's computer zips the copies out to whoever is on the list. For some reason it has not been zipping. Now it is.)

He does his thing; stethoscope, poke'm here, poke'm there... "DEEP breath... no, a really deep breath..." and I'm breathing so hard the wallpaper is starting to blister. Doesn't believe the girls figures perhaps.

Hems & haws and finally tells me: 'Get outta here. Come see me in three or four months."

So the physicians are all in agreement: I'm pregnant. Or mebbe not :-) But I'm certainly not suffering from a cancerous tumor. Oh, it's there. And it has already done its dirty work. But except for the back pain I am not suffering from it. It has not spread; it is not eating me alive.
This is GOOD NEWS . And I am happy to share it with you.

There is still the pain, of course, kept in check by a careful balance of pain-killers. If I try to do too much -- and I have, a time or two. I have a Magic Elixer called 'No Pain' that I can rub on the spot which does a nice job if the pain is not too large. But keep pushing the envelop and the pain will eventually break through. By the time it does, it's no laughing matter -- the magnitude is 'way out there and nothing works except a shot or more pain pills... which knocks me out. And if I'm not near a bed when that happens, it can be a major inconvenience.

But today was a good day. One I wanted to share with you.

---------------------------------------------------------------------

I'm still working on the Portable/Table Saw project. I wasted a week tracking down some sanding disks. Then we had a spate of rain (!!). Unheard of this late in the year. Then there were house chores... yada, yada, yada.

And the worry. Which is kinda funny.

I've got cancer. But I feel pretty good and find myself worrying about that. Think about it for a minute. The main problem is that I've not yet gotten to the point where I can shrug my shoulders and get on with my life. After all, Cancer is Bad. So I shouldn't be feeling Good.

Crazy, eh?

-R.S.Hoover

Thursday, June 4, 2009

On Engines



In response to one of Rocky's messages I mentioned a number of things
that can effect compression ratio. Sunday I go to check the mail and
there's this buncha guys peering in my window all saying pretty much the
same thing:

I don't see how ... (you fill in the blank) can have any effect on CR.

A minor variation on the theme was:

(Your favorite expert's name goes here)... sez to do it like ( whatever)
and never mentions (...various unmentionables...).

Please accept the following as a general answer for all.

CRANKCASE

The four holes in the crankcase that accept the cylinder barrels are called
spigot bores. The area around each bore is called the deck and serves to
support the cylinder. The deck of the spigot bores must all be the same
distance from the center-line of the crankshaft. This is something you
check before you start building any VW engine even when using a new
crankcase because sometimes the axis of the crankshaft is machined
slightly eccentric, meaning the main bearing bores are a little bit deeper in
one half of the crankcase than the other. Or more rarely, machined at a
slight angle, with the clutch-end being more to the left, the pulley-end to
the right (or visa-versa). Not often but it happens. So you check it.

With any USED crankcase the spigot bore decks will have been re-faced
-- re-machined to get rid of the shuffle marks. Good shops with the right
equipment always machine the case decks to match but if you buy a used
crankcase from a shade-tree mechanic or a shop that caters to the kiddie
trade you're liable to find almost anything. I've seen cases with as much
as sixty thou variation in the spigot deck height from one side to the
other... and almost that much on the same side of some cases, which tells
you the case came from a drill-press operation (ie, a shop that doesn't
have a milling machine).

Your jugs sit on the deck around the spigot bores. If there is any
difference in their height it will be reflected in the height of the cylinders.
And since the con-rod extension is relative to the center-line of the
crankcase, any variation in the height of the cylinders will show up as a
difference in the deck-height of the piston at TDC.

If that's not clear, make a drawing and work it out but the message here
is that you have to KNOW. You can't guess. You need to blueprint the
case and record your findings, whatever they are, because you're about to
build on that foundation and by the time you get out to the heads you will
have stacked up half a dozen components and even the smallest
variations will have become significant because of the stack-up.

Major point here is that there is always some amount of variation. With
an army of inspectors to insure the quality of every step in the
manufacturing process, for original Volkswagen parts the variations
would tend to cancel each other out rather than stack up. That's not true
with after-market parts. The only way to know what you have is to
measure what you got. Some guys call this 'blueprinting' and make a big
deal out of it but it's mostly common sense.

CRANKSHAFT

Set the crank up in vee blocks or with fitted bearings in a known-true
case half and check the length of the throws, even if it's a good crank
you've just sent out for a polish. Sometimes the grinder will have a bad
day and you'll end up with a crank having a slightly different stroke on
one (or more!) of the journals. So you check it to within the accuracy of
your tooling and record the results. Usually, cranks are pretty good.
Some of those cranks coming in from China are as good as any I've seen.
But some are trash. Ditto for a LOT of welded strokers aimed at the
Kiddie Trade, with examples of every problem you can name being
woefully common. You have to check and record what you find even
when any variation falls within acceptable limits because that variation,
whatever it is, will add to or subtract from the finished dimensions of the
engine.

CONNECTING RODS

To 'rebuild' a rod you re-bush the little end, hone the bush to spec then
pull apart the big end, use a surface grinder to remove a little metal from
the parting line, torque it back together and machine the big-end back to
a true circle relative to the little end. That is, you try to keep the distance
between the center of the big end to the center of the little end the same
as for a new rod fresh from the factory.

Sunnen honer properly maintained, skilled machinist... you can produce a
pretty good rod. Shops that cater to the kiddie trade... wetback labor...
worn-out or poorly maintained machine tools... Forget about it.

So what's the spec for a stock length rod? I donno... 137mm?
Something like that.

Doesn't really matter. (!!) What matters is that all four of your rods
must be of IDENTICAL length. That's what matters. Long or short,
you can deal with that but only if they are all the SAME.

But they won't be. There will be some variation in their center-to-center
length, center of mass and over-all mass. You'll take care of the weigh
differences during balancing but right now you need to know the
variation in their center-to-center length, which is pretty easy to measure
even with simple tools if you use one journal of a crankcase as your
center on the big end and a well fitted wrist pin on the other.

Con-rods are numbered. Use their number in your records when you
record the difference in their lengths. SOP is to identify the shortest rod
then simply record the differences of the other three. Good rods, you'll
be working in tenths.

What's a well fitted wrist pin? Oiled and at room temperature, you
should be able to slide the pin into the little-end with your hands. Once
in, it should fit well enough so that the pin takes at least two or three
seconds to slide OUT when the rod is held horizontally (and the pin is
installed flush). Slower is better. At running temps the forged mild steel
rod will expand more than the polished cast iron pin so a good fit is one
that is damned tight at room temperature. There should never be a
problem with the fit between the pin and the piston because the
coefficient of thermal expansion for aluminum is MUCH greater than for
cast iron; at operating temps the piston will always be an easy fit on the
pin even if they are locked together at room temperature. (You generally
heat the pistons to install/remove the pin.)

A lot of rods aimed at the kiddie trade or used by lo-buck rebuilders
aren't even overhauled. They just knurl the bushing and hone it back to
size and merely hit the big-end with a hammer before honing if they
bother to hone it at all. Shop by price, you'll end up buying junk. Good
shops are proud of the quality of their work, offer no objection if you
want to mike a part now & then. Ditto for good dealers. The other kind
don't want anything to do with real mechanics. And get their wish :-)

PISTONS & CYLINDERS

Pistons & cylinders are manufactured individually then sorted according
to their finished diameter (for jugs) and weight (for pistons). The
different sizes and weights are identified by dots of colored paint on the
pistons.

In manufacturing a cylinder barrel the raw casting is first machined then
the machined barrel is honed to remove the tool marks. In the process of
machining a given number of cylinders, the finished bore will become
gradually smaller as the tool-bit wears down. When it gets to a certain
minimum size they stop the machine and set it back up with a new boring
tool. The point here is that the inside diameter of the jugs being
produced will fall across a certain range of diameters. This is normal.

The honed jugs are measured and divided into groups according to some
standard deviation in their diameter, typically about a thousandth of an
inch. But even with that small a standard, with four jugs from the same
size-group you can expect to find a variation in their diameter. It won't
be much but you need check it.

Volkswagen used cast aluminum pistons from permanent molds. The
density of cast aluminum varies slightly according to how much metal is
in the smelting pot, its temperature and how long its been there. The
castings are then machined to a given diameter, for the grooves where
piston rings, for the wrist pin and for the top of the piston. All other
surfaces are usually left as-cast. As with all machining operations, the
finished dimensions will fall across a range of sizes.

The combination of differing density in the aluminum alloy and variations
in the as-cast dimensions causes VW pistons to vary in weight by as
much as an ounce (!) Even by 1930's standards that's a bit much so the
pistons get sorted into three weight groups with each group having a
maximum variation of ten grams.

The nominal dimension of the piston (i.e., its size group) is stamped on
the top and a dot of colored paint is used to indicate which direction its
actual dimension deviates from the stamped figure. A dot of colored
paint is used to indicate the piston's weight group and a plus or minus
symbol is stamped into the top of the piston to indicate if the piston's
weight is above or below the nominal weight for that group.

The pistons are divided into groups according to their weight and within
each weight group, are divided into groups according to their diameter,
allowing them to be matched with suitable jugs, fitted with rings and
packaged for shipment. Stock jugs used to be available individually;
nowadays all you'll see are sets of four.

But your carton of new pistons & cylinders may arrive as a grossly mis-
matched set of junk. Here's why: Some after-market retails -- or the
clerks who work for them -- tear open the boxes and shuffle sets around
to make up sets having the largest bore diameter and identical weight
markings. Some dealers even brag about this in their advertising,
referring to such sets as the 'pick of the litter' that need no further
balancing. And sell such sets at inflated prices.

It's all bullshit of course. With a weight group encompassing ten grams,
with two divisions and a mark for high or low the best you can hope for
is a spread of 2.5g... about 25x worse than a real balancing job. (Using
an inexpensive electronic scale for measuring and a Dremel tool for
removing metal, the average novice has no trouble matching four pistons
to within a gram or two.)

But the most interesting point of all this is what happens AFTER those
sets of pistons have been pawed over by the clerks. They get tossed back
into the boxes willy-nilly and sold to unsuspecting suckers, including
other retailers.

The tricky bit here is that you can't balance a set of pistons if they span
TWO weight groups. Pistons are provided with extra metal in the form
of 'balancing pads,' areas from which you may remove metal without
effecting the strength of the piston. But the maximum amount you can
remove is only a few grams. That isn't a problem when all of the pistons
are from the same weight group. But with MIXED weight groups you're
liable to see as much as 20 GRAMS difference across your four brand
new jugs. Not only does that violate the factory spec of 10g, the
difference is too large to be balanced out - - there simply isn't enough
metal that can be safely removed.

You just paid good money for a set of new jugs that are junk.

But this is about compression ratio so let's get back to that.

First thing you gotta do is examine your new set of P&C's to make sure
they are of the same size group (ie, the variation of diameter) and within
the same weight group. That is, all four of the jugs in the box should
have the same color code for dimension and the same color basic color
code for weight group. The code for plus & minus doesn't matter
because you're going to have them re-balanced to a finer standard of
precision (i.e., typically +/- 0.1g across a set of 4).

You should do all that before you buy them. And yes, you can get
royally screwed when buying through the mail. No, I won't recommend
anyone -- I've been sued both ways on that one, once because a guy was
unhappy with someone I recommended and another time by a dealer
because I DIDN'T recommend him. So go fish. And good luck.
Because getting a set of P&C's that hasn't been tampered with is just the
start of the story.

Once you have a set of P&C you'll need to put identifying marks on the
jugs and record the marks and the dimensions in your notes. I file
notches in the flat area of the upper-most fin. When you have more than
one engine in the shop at a time, keeping their parts separate can be a
problem. I use a series of adjoining notches to identify the set then one
to four additional notches, spaced apart, to identify a particular jug within
a set. The notches are cut with die-grinder as soon as I open the box.
The pistons have to stay with their particular jug so you need to put a
matching mark or number on the underside of that piston. I use a
vibrating scriber.

Begin your measurements with the distance between the deck lip and the
top of the cylinder barrel. The easy way to do this is to just stand the
thing on its head and use a surface gauge to find the tallest barrel then
record any difference in the other three. Here again, you can expect
some small variation.

Barrel length is an especially critical dimension in an horizontally
opposed engine since it is the foundation of the valve train geometry.
This dimension is even more important in horizontally opposed engines
like the Volkswagen which depend upon head studs (or stays) to
maintain the seal between the cylinder and the head since any difference
in the length of the barrels will impose an asymmetric load on the sealing
surface leading to compression leaks.

After measuring the length of the barrels the pistons are removed and the
pin height is measured. Follow the same general procedure; put the
piston, head down, on a surface plate, use a gauge to find the tallest then
record the difference between it and the other. (As a point of interest, in
most cases there's nothing to record - - the dimensions match to within
less than a thousandth of an inch and an amount that small is generally
not significant. What I'm really looking for here is any radical departure
from the norm.)

The rings get removed and a lot of other work gets done but we're only
talking CR here so I won't go into the other stuff.

CYLINDER HEADS

As with the jugs, when measuring the heads you must first identify them.
Through the course of assembling an engine the heads get a lot of work
done to them and you need to keep good records. I stamp numbers on
them, over by the right-hand exhaust stack (right-hand looking into the
chambers, push-rods down). Doesn't really matter how you identify them
just so you do. I use stamped numbers because in prepping a set of
heads I usually replace some of the guides, run them through the blasting
cabinet to roughen up certain areas then open up the chambers, unshroud
the valves and do a few other things, most of which will destroy any kind
of temporary markings.

On the chamber-side of the head casting you will find either a fully
machined flat area surrounding the chambers (old style heads) or six
machined bosses, three to each chamber. The horizontal plane defined by
the machined surface is the base-line for all of your head dimensions.

You need to know the distance from that horizontal plane to the sealing
surface of the combustion chamber. More specifically, you want that
distance to be as close to identical as possible for both heads and, within
a head, for both chambers.

This dimension can be all over the map if the heads have been opened up
by a schlock shop. Good shop, any variation should only be a few tenths
(ie, ten-thousandths of an inch) up to a max of half a thou (ie, fifty
ten-thousandths). Shlock shop, using a cutter in a drill press, you won't
believe the crap they turn out.

This dimension is especially critical in the fabrication of a good VW
engine. If this distance varies by more than two thou between the
chambers of the same head, or by five thou between a pair of heads,
have the heads fly-cut by the minimum amount needed to arrive at a
uniform figure for all four chambers.

With measurements for the case deck height, barrel length, rod length
and piston head height, and knowing the compression ratio you are
planning to use, measuring your chamber volumes tells you how much
you will have to open them up to achieve the desired compression ratio.
Indeed, once you've nailed down a few dimensions, setting up the correct
compression ratio becomes something of a no-brainer.

And somewhere about now you'll realize this message wasn't about
compression ratio at all :-)

- - - - - - - - - - - - - - - - - - - -

There are two main reasons for doing the work described above. The
first is to be able to identify good parts from bad parts. You can't make
this determination by price nor the fact the part is new, rebuilt or
whatever. Nowadays there is so much junk out there the wiser course is
to assume you're dealing with shoddy goods until its specs prove
otherwise.

As you progress through the measurement of the parts you begin to see
ways in which you can combine those parts so as to arrive at the most
dimensionally-uniform result. For example, a slightly short throw on the
crank can be combined with a slightly long rod. The same is true for the
jugs and the heads in that some combinations may be used to cancel out
dimensional variations.

A nice point to keep in mind here is that the 'assembly' of a 'paper'
engine is an arm-chair activity. You may take as long you wish, shuffling
the numbers about in every possible combination until you arrive the one
that makes the best possible use of that particular set of parts.

OF THAT PARTICULAR SET OF PARTS...

Did the light-bulb come on over your head? You see, the typical engine-
builder can only afford ONE set of parts. And as much as I hate to say it,
if you simply bolt them together the odds of getting a good engine are
vanishingly small. Oh, it'll run. Veedubs are robust little buggers...
ANYTHING will run. But if you simply throw the thing together it will
not run as well as it should nor last as long as it could. And you won't
know the difference.

But I'm not a machinist... (I heard someone shout).

Neither was W. Edwards Deming. He was a statistician with the Bureau
of the Census. (Never heard of him? Your loss.)

The truth is, you don't need to be a machinist to build a better engine.
You can do that by simply taking a few measurements and keeping good
notes. That's enough to keep you from building a total piece of shit.
When you subtract the POS Probability Factor from the engine building
equation you AUTOMATICALLY end up with a better engine. How
much better? On average, about twice as good. Yeah, I know... nobody
else believes it either. Except for the guys who have done it. (Didja read
my article on dialing in your cam? Ditto.)

Up to you. It's your engine.

-R.S.Hoover

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