You should use an updated transmission instead

Question:

I have a 1962 Oldsmobile F85 Cutlass convertible that used to have the 215 cid aluminum engine. I would like to install a small block Chevy engine and need to know what modifications are necessary to make this change.

I have the original automatic transmission that came with the 215 cid engine, which I think is the C4 automatic.

Will this transmission mate to a small block Chevy engine? I have access to a 307 cid Chevy engine for this project. Would this be a good choice?

Answer:

The Hydra-Matic automatic transmission that came in your 1962 Olds will not bolt up to a small block Chevy engine. I could not find an adaptor to mate your vintage transmission to a Chevy block. Most people want to do the opposite— mate a more modern transmission to the car’s original-type engine and there are

adaptors available for this. You will save yourself a considerable degree of grief if you use an updated transmission that readily mates to that 307 Chevrolet engine. The transmission that came in your Oldsmobile was, I think, called a 4S Hydra-Matic. C4 is the designation that Ford used for one of its more popular automatic transmissions.