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Posted by Bob Hoover on September 19, 1999 at 14:47:58: In Reply to: VW engine types posted by John Gencarelli on September 19, 1999 at 12:06:27:
---------------------- Dear John, In VW lingo, 'Type' refers to the vehicle. The Type I is the sedan (ie, bug, beetle, whatever), Type II is the Transporter (ie, bus, microbus, Kombi, etc). Type III is the fastback, introduced in 1965, Type IV is the fastback's replacement, introduced... I donno when (1972?). But when it comes to engines there's really only two. The early engine has a magnesium alloy crankse and was used in the Type I, II, and III vehicles. The later engine has an aluminum alloy crankcase and was used in the Type IV and the later models ('72 thru '79) Type II's. With different heads, the Type IV engine was also used in the Type 914, the VW-Porsche. The early engines were mostly fitted with upright blower housings. But when installed in a Type III, they used an axially-mounted blower. (VW's Industrial Engine Division sold them both ways.) The Type IV always used an axially-mounted blower... except when that engine was used on a fire pump or whatever, when it might appear with a Porsche-type blower and upper plenum chamber. The early engine comes in two basic flavors, those having the dynamo tower cast intergal with the crankcase and those on which the tower bolts on. The early engines, commonly called '36 horsepower' [although they include 20, 22 and 25hp models] use a different crankshaft and the internal parts are not interchangible with the later engines. The later engines, from the so-called '40 horse' on up (ie, the 1300cc engine) all use the same internal components. The only thing that changed was the jugs and the heads. The jugs got bored out from 77 to 83 and finally to 85.5, increasing the displacement from 1300cc to 1500 and finally 1600 (the actual displacements are a little bit less... the usual automotive bullshit applies as to displacement & power :-) There were about 22 different heads used on the early type engines. They fall into two broad catagories -- Single Port and Dual Port. Dual ports crack like a bitch but flow better at high rpms. Within each head type there is a variety of valve sizes, from itty-biddy ones used on the fuel-injected 1965 Type III engines to enormous things used on the alcohol-fueled Brazilian beetle engine. The last German-built VW engine of the early type was produced at the Emden plant in 1982, meaning the youngest possible engine is already 16 years old... and many are pushing fifty. The point here is that whatever engine you've got, chances are it has been overhauled, meaning you haven't any idea in the blue-eyed world what's inside the thing. If you're interested, you can check the serial number to determine in which vehicle -- and which year -- the engine was originally installed... assuming you have a serial number. Universal Replacement crankcases came without serial numbers and many present-day VW engines have been built on new cases. New Type I engines are still being built by VW de Mexico and are available from a number of suppliers for about $1000. This is like finding money since the parts to build an all-new engine cost more than that. Indeed, the cost of a proper OVERHAUL is more than that :-) The only major distinction on the basis of voltage is the number of teeth on the 1000 flywheel. The ring-gear for a six-volt starter has 109 teeth whereas 12v uses 132. The only other electrical components on the engine (dynamo, ignition coil, choke heater element and anti-dieseling solenoid) are marked as to their voltage... which has nothing to do with the engine itself since all of these components are demountable and come in either six- or twelve-volt 'flavors', meaning that if you got the one but want the other, just unbolt the thing and replace it. As to EXACTLY what engine you have, it's kinda hard to say since you didn't give us any hints :-) See if you can find a copy of Tom Wilson's excellent 'How to Overhaul Your Aircooled Volkswagen Engine'. Costs about fifteen bux and is available from J.C.Whitney and all of the after-market VW retailers. It'll cut through the bullshit like a chainsaw. If you want a good ride out of a VW engine, don't get suckered in by all the horsepower talk. VW engines use basically the same heads from the 1300 on up and the maximum SUSTAINABLE output of any aircooled engine is determined by the fin-area of the heads. For an early-type VW engine the SUSTAINED OUTPUT limit is around 50 hp... if the weather is cool and you've got all the tin-ware in place, including the air-vanes in the blower housing. You can increase the displacement to some really ridiculous figures and generate up to 300 hp if you spin it fast enough... but only for a few seconds, after which the laws of physics tap you on the shoulder. Your engine's service life is determined by how many times the laws of physics comes to call. Keep the output low, you can have a reliable, drip-free ride for a hundred thousand miles or more. Push the envelope (and twist the handle :-) and you'll discover automotive reality follows an inverse-cube relationship -- 2x the power means 8x the wear. Cruel but true. If you do all your own work you can run whatever turns you on but if you gotta pay somebody to keep it running, a high output engine can get expensive in a hurry. Lotta fun, though :-) -Bob Hoover
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