The other day I was talking to a friend who is building a 20B with some extra intakean exhaust porting. He pointed out that he had switched out his stock exhaust sleeves with those from a TII. He said they were bigger of the factory. I haven't read anything about this mod on this board or the RX7Club.



Can somebody confirm?

Engine is being streetported and will run non-seq turbo's in my FD.

 

from what i've seen around the forums, people swap Rx-7 Turbo rotor housings onto Cosmo engines because the exhausts ports are bigger from the factory. i'm not sure how much of difference this makes since you'll be porting it anyway, but yes, the Cosmo exhaust ports are smaller.