I have 1980 RX7 and I want to eventually go into road racing. It has a 12A engine in there and I am thinking of upgrading. What is the best engine I could put in there without having to hack the engine bay. This is not a daily driver vehicle. Thanks I wouldn' mind putting a turbo on there either.

 

a first gen 13B out of a GSL-SE will fit as well as a sencond get 13B N/A and turbo. I know you will need a couple parts of the 12A to make the 13B fit. Small stuff like the front cover, and I think the oil pan. Its been a while since I looked into that so the best place to find the info is the first gen forum. They will know all about it. There is even a guy there who has a turbo on a blow-through carb.

 

well ... 13B definitely is your BEST option to the 12A (although it will depend on the class you plan to run in)

however, just to correct one thing ... the 12A oil pan doesn't fit the 13B.

you'll need to get the SE oil pan for any of the newer 13B engines, plus you'll ave to use the 12A distributor and water pump on them as well