a friend wants to build a good but resonably priced engine for his 914. he has a 2.0 bus engine and a 914 1.7 engine. we're looking into the best combo. to build

1 what differences are in the bus vrs. 914 2.0 engines (deside the heads and windage tray?)
2 does a BUS case have "GA" #'s and the grooves for the windage tray?
3 will 94mm or 96mm cylinders and/or the 71mm (2.0) crank fit the 1.7 case w/o machining?

mike

I don't know about the bus engines, but I do know that I have a 1.7 case with a 2.0 crank and 96's, I didn't need to do any machining except for an align bore.

so most likely the bus 2.0 has same bearings and other charicteristics (der... spelling?)

Some bus cases had a mechanical fuel pump and you would need to block that off. Also, you would have to tap and drill for the oil dip stick.

Talked to Jake about bus cases one time. He suggesed that a bus motor is more likely to be beat up and out of alignment due to the heavy work a bus motor has to do compaired to a 914 motor. Jake likes the 1.7 cases for his big builds.

Use that one.

Mike, there are a few differences, use a 1.7 case, there plentiful

That offer above sounds good

While the 2.0 bus crank is identical to the 2.0 914 crank, the rods are heavier. I measured 914 rods at about 760g (IIRC) vs. 790g to over 800g for the bus rods. This makes a BIG diff at redline...

I have a 2.0 bus engine in my 73 right now, which I didn't put in ... it's a boat anchor of a motor, and although I have to give it credit for not dying on me (despite several attempts to do so, which turned out to be just warning shots).

I know the compression is significantly lower, and comparably so is HP (though I think you might gain low-end torque - if you find a decent bus motor in the first place, unlike mine). If you plan to change all that and just use the case, then ... more power to ya.

The problems I'd had with mine were initially based on the fact that the 1.7 Djet wasn't working at all on that poor motor ... and the fact that it was only running on 3 cylinders for a long time due to something broken on the rocker arm assembly. Which broke again, in a different place, later ... lots oil. Speaking of that, I get ~500 miles to the gallon ... of OIL.

BTW, the dipstick is in the exact same place on the bus motor as a teener 2.0.

When I take it out, it's going to be donated to a VW parts guy in town. I've had enough of this poor ol' thing. My recommendation? Stick with a 1.7 for sure.

- Nelson

All the cases are interchangable. The 2.0L bus engine has low compression and huge dishes in the top of the oistons. Bus heads have smaller valves. Have the heads redone by Len Hoffman with bigger seats and valves. Have the 2.0 cylinders bored to 96MM and inatall KB pistons from Jake . Add a jake cam and you've got a great engine.

The flywheel and clutch are different. The bus clutch is 228mm. The flywheel is lighter. This is what I run in mine. I further lightened it. The center of the flywheel must be bored for the pilot bearing.