I am rebuilding my 79 sa rx-7 and I needed a new rear housing. The right housing in the picture is the front housing off my engine and the left housing is another front housing I want to use for the rebuild. Question is can I use 2 “front” housings?
also why are the exhaust ports different and will they work?
I will be using headers and not the thermal reactor so the extra bottom ports shouldn’t matter right?
If I port the exhausts to make them match will it run ok?

 

No, the air ports on the bottom will not line up with the thermal reactor (exhaust manifold).

 

You are correct, however I will be using an aftermarket manifold therefore I can just block off the ports?

 

Having new information changes things. Yes, you can block the ports.