I am looking to have an engine (I think from a 79’) as a back up in a racecar. I would like to have it for the most part ready to drop in if my current one dies. I have an 85’ which is gutted and stripped of everything that I don’t need. I currently have a bad 12a that I can pull parts from to install on the 79’ . I am running a stock stripped intake with a modified Nikki carb.

It looks like there are two ways to do the swap.

1) Switch to a lightened flywheel to be able to use the same 85’ clutch/pressure plate. I would still use 79’ front and rear counter weights.
2) Stick with the 79’ engine as is and buy a 79’ clutch to bolt up to the 85’ Trans (this is what I am panning on doing)

Questions:
-Will the 79’ engine bolt up to the 85’ trans?

-Will the 85’ front cover, water pump, and oil pump bolt up to the 79’ and can I now use the distributor from the 85’?

-Are the oil pan and oil pickup swappable?

It looks like the 79’ and 85’ intake ports are the same

 

1. the 79 12A will bolt up to any RX-7 trans from 79-85

2. the pan and pickup and pickup are interchangeable and identical.

3. both are 4 port 12A's.

 

Done it a couple times. The only difference between an SA and an FB engine is the emissions control layout and the changes in emissions port location/function. In a non emissions application, they're interchangeable.

You're on the right track with the clutch.

 

I've got a 6 port 13B and a 4 port 12A engine that I swap back and forth in my SA22.

I think the motor mounts are different between the two, but I just keep the clutches and motor mounts with their respective engine.

I do have seperate carbs for both the 12A and 13B and I don't have any emmissions for either.

I also have seperate headers and catback systems for both....


I guess it would help if I knew the origins of the mysterious 13B engine. haha

 

Any one have a SA front counter weight they want to sell?