The pancake engine
The Type III's powerplant is often called the "pancake" engine. No, it doesn't go great with maple syrup (although mine has transported me to a tree-tapping demonstration!); think "as flat as a pancake."
A fuel injected pancake engine & transaxle.
Here's what a brand-new Type III pancake engine looks like, courtesy of Paul Colbert.
An early single-carb engine.
Paul spotted it for sale in Florida for $1500 a few years back. Yes, those NOS finds are out there somewhere. Keep looking!
(Re)building the pancake engine
Derek van Veen (VANVEEND@cgs.edu) offers these experiences on rebuilding a pancake Type III engine, with some particular suggestions for fuel injected models. This is followed by a bit of a rebuttal--and a somewhat different set of experiences--from Jim Adney.
BUILDING THAT "SPECIAL" ENGINE FOR YOUR TYPE III ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Building a nice new motor for your ride is something that (almost) all VW owners look forward to--however, for the Type III owner, this can be an especially daunting task. First and foremost, you should know that with VW motors, just as with fashion, one size does *not* fit all. As the Type III uses a "pancake" or "suitcase" motor, as well as runs on the Bosch D-Jetronic fuel injection system, there are many aspects of the Type III powerplant that run contrary to traditional VW wisdom. One of the major obsticles to your new motor, especially if you decide to run a full-flow oil filtration system (a *very* wise investment), is the rear cross-member that supports the back of the motor. Type I motors simply hung the engine off the transmission, and therefore don't have to compete for space around the oil pump. The Type III owner, on the other hand, has the cross member *and* the fan shroud with which to compete. As a result, all those "universal" oil pump covers that allow for plumbing a full-flow system, are not, in fact, universal. To mount a full-flow oil pump cover, you have several options as to how to deal with the fan shroud, but only one for dealing with the crossmember. In the case of the latter problem, you have to hack out a square section, plain and simple. You can usually take a piece that's about 1" deep by 2" wide off of the member, and that will be enough to clear the pump cover. For the fan shroud, on the other hand, you can do one of two things: A) Grind away the webbing and a bit of the shroud itself, or B) Shim out your fan/pulley assembly and the fan shroud itself, and only grind away the shroud webbing. Either way, you're gonna have to do a bit of grinding. It also helps if you grind a little bit off of the hose connection barbs (the brass bit where the hose attaches to the cast- iron pump cover), but not too much, as you need to have burst resistance. Another piece of VW wisdom that is a load of B.S. when applied to the later Type IIIs, is the belief in semi-hemi cutting your cylinder heads and shimming out your cylinders to lower your compression ratio to 6.9:1. On a D-Jetronic motor, the end result of this exercise is lousy mileage and loss of power (not to mention hesitation and backfiring). You should always be running at least a 7.7:1 compression ratio and a fuel pressure of 28psi. *Never* mess with the heads of a Type III with fuel injection--this means that semi-hemi cutting, porting, running bigger valves, and running hotter cams or ratio rockers are all Verboten. As the D-Jetronic needs to see a certain manifold pressure to run correctly, fooling with the rate of airflow or the compression can have anywhere from annoying to disasterous results. So keep it stock! If you are going to build a bigger engine (please, never more than 1776cc's, as the car can't handle the heat buildup), just make sure that you run the correct size injectors with your motor (e.g. 1.6 -> 1.7 -> 1.8 litre injectors), and maintain the holy 7.7:1 compression ratio. It is alright if you run a bit over 7.7:1, as long as you check your emissions for the proper fuel/air mixture. Finally, when installing your engine, be patient. Unlike those lazy Bug owners, Type III owners have to make sure that the engine is correctly seated in the crossmember hangers, as well as making sure that the flywheel/clutch assembly lines up with the splines on the transmission. Derek van Veen (VANVEEND@cgs.edu)
Now, here's what Jim has to say:
I would be the last person in the world not to take Gene Berg seriously, but I have some trouble with this. In one of Bergs later price lists, he said not to use the semi-hemi on FI type IIIs because they already have a knock sensor. Well, there is no knock sensor on any type III. Perhaps he was thinking about the cyl head temp sensor, but this would not have the same effect. Fortuanately, or unfortunately, depending on your point of view, this warning came too late for me to agonize over it. I had already semi-hemi three sets of my heads and built two of them into engines which had been on the road for a couple of years. These two cars are still on the road and running fine after more than 5 years. All of my rebuilds have been stock P/Cs, cam, and valves, but completely ported per the Bill Fisher book; I later got hold of Bergs porting instruction in which he revises some of his earlier work in the book--I haven't put any of these changes to the test yet. In addition I add a Berg counterweighted crank and have them balance everything. Here's what I have found: I can't see any big difference between the before and after. I certainly feel more comfortable revving the engine much higher, and I THINK there is an increase in power due to the porting, but this is subjective and subject to dispute. I note no change in gas mileage, and I monitor and log EVERY(!) tankful. There is no hesitation except that which was there before with the stock engine. My own current daily driver was a lemon that I purchased because the PO couldn't afford to keep paying me to try to fix it every weekend. I'm afraid that I have managed to find one insidious problem per year in the 5-7 years that I have owned it. I was worried last fall that the semi-hemi problem was coming to haunt me, but it turned out to be the pressure sensor (leaking bellows!) The car just keeps working a bit better year after year, but I have not had any problems related to the mechanical parts of the engine itself. This is not to say that it works up to Berg's standards. It is quite possible that Gene would not like any type III D-Jetronix. Gene's standards were very high, but I haven't see any signs in his published materials that he spent much time working with type III D-Jetronix. It's also possible that he did, but his test car had one of those problems that can go unrecognized/undiagnosed for years, overshadowing all his testing. Face it, our cars have a reputation for being troublesome. For the record, I've been driving type IIIs exclusively since 1968 and doing all my own repairs since about 1970. My wife has been driving exclusively type IIIs since we were married in 1974 until this winter when she finally succomed to the siren song of winter heat and got something new, water cooled, american made, and warm. Of course I did all the repairs on her type IIIs, too. On top of the family's daily drivers we also have several stored for occasional use. All my type IIIs have been squarebacks. In the meantime I have made a bit of a sideline business of repairing type IIIs for other owners, of which there are very few any more. Jim Adney (jadney@vwtype3.org)
As you can see, engine building is not a matter to be taken lightly! Do your homework...