making a 2 liter, Cylinder Question Options

[malcolm2]

I plan to buy new 94mm dished pistons for my bus project. AA has the set for $250.

They also have just the pistons for $140. Should I consider having the 1.8 cylinders done to accept the 2.0 pistons?

Not sure about the cost yet. The shop I planned to go to has been closed for the Holidays. So his charges might answer my question.

But what does the group think? Especially the Bus people. They have recommended going with the 2 liter vs the 2056. So here I am with more questions... (IMG:style_emoticons/default/piratenanner.gif)

Would the stock, honed 1.8 cylinders (unknown mileage) be better than new from AA?

[malcolm2]

My original thought was 96 mm, after a few posts hearing from long time bus folks, i decided to go stock 2.0. And yes, using the dished pistons to keep the CR to stock as well. IIRC stock bus compression ratio was 7.3:1.

Still have work to be done, I hope my machine shop is enjoying his long holiday. It is killing me.

[Miguel K R]

Sorry for the wrong information about the need to machine the crankcase and heads for the 96mm cylinders.
Several years ago I started with a 1.8L and as I was told that the 96mm cylinders were thin, I decided to buy 2L rods and a crank, and used 103mm cylinders with JE pistons to get a displacement of 2336cc. That engine was recently removed from my 914, which is going to get a 3.6L engine, so the Type iV will go to my VW Notchback.

I do have a VW bus with a 2L engine, without dished pistons, running on two 40 dual Dellortos.
Probably the gas you have in the US has a lower Octane level than in Europe ...
When VW designed the engine for the Bus they used dished pistons to reduce the compression ratio and thus avoid overheating in a heavy Bus. I guess that the lower compression ratio also had to do with emission controls in the US (VW engines, and Porsche 4 and 6 cylinder engines in the 1970's were sold with less horsepower in the US than in Europe).
I do not know how strict the emission controls are in the US for a BUS which is now some 45 years old ...
When the 2L Type IV engine was developed for the 914, dished pistons were not used, to increase the compression ratio. The heads were redesigned with the sparkplug repositioned (most people say this was for a more efficient burning and increased power... now I wonder if this was also to avoid detonation), and injection was used, instead of carburetors.

If you will be driving the bus in hot summers, on mountains, and loaded, you should use the dished pistons.
If the Bus will have a lighter use, you may consider using pistons without the dished area, to give you more torque and power.

Miguel