Engine Swap Info.

I've started collecting a few tips on either using a Corvair engine in other cars, or putting a different engine in your Corvair.

Corvair engine into Corvair.

So, you have a Corvair already and want to swap a different engine in? Generally speaking any basic Corvair engine will go in any Corvair, but there are a few details to be aware of:

Clutch and Flywheel.

From Seth Emerson and Stan East:

Stan East writes:
BTW the clutch cover for a Vega is, you guessed it a Corvair minus the ring gear. Now that Ford owns Cosworth do you think they might bring back the project?

--Stan East


Seth replies:
And, in case anybody cares, the Nodular iron Flywheel for the Cosworth Vega bolts to the pre-86 V8 and V6(90) and allows a Corvair clutch to be used - For you converters out there!



Clark Hartzel wrote this to help sort out which bellhousing you want:

The Chevrolet part numbers started out 625xxxx numbers and mysteriously changed to 37 or 38xxxxx numbers later on. If your bell housing has a 625 number it is definitely an early model. All Corvair bell housings are the same distance from the engine to the differential and have the same mounting hole patterns. The only difference (other than stick or Powerglide) is the seal surface machining (same bore). When they stroked the crank in 1964 the seal and the flywheel face moved .070. Put a seal in your bell housing and mount it on the engine. Look at the seal and the end of the crankshaft and verify that the seal is on the O.D. and that the housing or seal surface is not sticking out past the crankshaft where it will get rubbed by the flywheel. If everything clears, mount it and don't worry about it. If the seal or bell housing sticks out past the end of the crank you will have to remove the seal, machine the face deeper and put a spacer under the seal face to duplicate the later housing. Or find the later housing. Remember whatever engine you are using to match the flywheel and clutch with the engine not the car. Late models use stepped flywheels and bent finger clutches. Early models use flat face flywheels and flat finger clutches. That .070 difference I mentioned is what determines which clutch and flywheel to use.

Clark Hartzel, former CPF curator and keeper of the engineering drawings


Frank F Parker writes:

In preparation for my Northstar conversion, I have removed the vair engine/trans and rear suspension and weighed them. Be interested if my weights are close to what others have seen or noted in the literature. All weights are in pounds.

hub/arms/brakes (no spring, shk, axles)60/side
Trans support23

Someone told me individual weights of trans is 78 and diff is 115. That would put engine at 263.
[Note: I asked Frank about the completeness of the engine when he weighed it. The engine was out of a Corsa, with shrouds, manifolds and starter, but no air filter or exhaust system. I believe Frank's weight for the engine is low, the weight in the 1961 shop manual for the complete engine is 358 pounds. The same specs list the 4 speed transaxle weight at 136.5 pounds.]
Total weight of eng/trans/diff/susp is about 636 pounds.
Northstar 4.6L dohc motor weighs 334 pounds or 71 more than Vair.

--frank parker
65 vair/98 STS mid mounted project car

From a posting on the FastVair list, some weights for other transaxles (in pounds):

VW Bug 4 speed transaxle71
VW Bus79
Corvair 4 speed (probably '66 up box)149
901 Porsche89
915 Porsche109
ZF (Pantera)135

Finally, check out this list of engine dimensions and weights from Dave Williams of the hotrod list.