Chevy Corvairs were built from 1960 to 1969. There were 2 body styles, early and late (sounds like our buses). The early Corvairs were somewhat smaller and more square (they were built from 1960 to 1964). The late ones were built from '64 to '69. The early engines had a lower horsepower rating (I think it was 80 hp).
From 1964 through 1969 Chevy increased the horsepower by making the connecting rods longer and enlarging the diameter of the pistons. Now the motor put ouy 110 hp. You could also get a 140 hp motor which has 4 carbs and a 180 hp turbocharged engine. Both of these, the 140 and the turbo, are not what you want to install because of their slower torque curve, making the 1965 through 1969 110 engine ideal for the Transvair kit.
You use the Corvair transmission and differential for the conversion kit. You can use a 4 speed or an automatic transmission called a "Powerglide". This is a 2 speed transmission and it's what I have run for 8 years. One of the reasons I went this route is because the kit is cheaper for the auto and easier to install, plus there is a lot less things that can go wrong: no clutch no pressure plate, throw out bearing etc.
When I say it just bolts right in I mean it! The only thing you have to do as far as modifing anything is the engine compartment has to be cut out square, which is easily done with a Sawzall and a metal blade. The front of the transmission hangs in the same stock location as the VW transmission, the kit has an adaptor that makes this possible. The stock VW CV joints and axles are used and they bolt right up to the Corvair differential with the kit's adaptor plates. The rear of the engine hangs with the kit's engine mount which bolts right up to the stock VW locations on either side of the motor. It comes with everthing you need and everything fits perfect, wire harness and all.
This motor is bullet proof. It has hydraulic lifters, dual carbs and your horsepower doubles. When the kit is installed it looks stock, but runs like a bat out of hell. One thing I like is that now I never have to adjust the lifters or re-torque the heads. When it had a VW engine I was going through an engine a year. I have had this set up for 8 years now and the only thing that I ever had go wrong is I dropped a valve seat. Also I don't have to drive in the slow lane anymore on the freeway, I can drive 80 to 90 mph. My favorite thing to do is spot a bus the same year as mine on the freeway, pulling up next to it and then just leave it in the dust. Plus, the way the 6 cylinder, dual exhaust sounds: it's so cool!!!!
To do this installation right you should start out with a rebuilt engine and transaxle which could run anywhere from $2,000-3,000 depending on how trick you want it.
The kit costs $600 and comes with everthing you need including instructions with good pictures
Corvair parts are not rare. They are everywhere
and can be picked up at a good price. The 2 biggest parts suppliers
are Clark's Corvair in
Shelburne, Massachusetts, USA and the Corvair Underground in
Oregon, USA. They make everything you could ever need for
rebuilding a Corvair engine.