I know this doesnt have a whole lot to do with single turbos. I have seen a lot about switchin engine parts between the S4,S5, and FD. Say I had a single turbo TII wanting to make 400 reliable hp and wanting it to have a pretty high redline what would be the best buildup? I know this is a vague question, but i havent seen it where anyone really goes over the cons/pros of switching parts.

 

S5 and FD engines are VERY similar. they can rev about the same. same weight rotors, etc . most people switch to 89+ engines as they are higher compression and lighter weight rotors. FD engines have the biggest ports of a USDM turbo engine. TII engines can make 500hp just like a FD engine

 

But then again, if you want to run extremely high boost, the FD has better compression rotors than the S5. (like 25+ psi)

 

So the FD has lower compression rotors than the S5 TII?

 

no they have the same compression

mike

 

Yeah they are both the same (9.0:1)
I got mixed up with the S5 NA having a 9.7:1 compressoin ratio.
Sorry, my mistake.

 

Well here.. Since your not really answering my question, can you give me all the pros and cons of common switchin? Such as rotors, side housings, etc.....

 

use the search function and it will all become clear....

https://www.rx7club.com/forum/showth...ghlight=rotors

 

i just built my '87 t2 engine with fd rotors, thrust bearing assy., stationary gears, rear oil pressure reg. and tension bolts. the thrust assembly looks alot beefier and i wanted the rotors b/c of the loss in weight for higher revs. seems to be working great so far. it might be a good idea -if you are running reletivly low boost values- to use the n/a rotors from a 89-91. these are quite a bit less $$ and still weight the same as an fd for the revs. make sure your get the frnt counterweight. i noticed no difference between the rear counterweight on my rb flywheel and the auto fd rear c.w. i bought fot the conversion.
justin