Has anyone ever put a twin scroll turbo from an FC onto an FD, or have info or opinions on what this setup might be like?

 

might want to move this question to the Single Turbo Section of the forum. Might get some good feedback in there.
There's alot more involved than just puting a single turbo on the car.

 

i dont see why anyone would want to do so?

 

IIRC, the FC turbo is only good for around 300whp. Our twins are good for 350+ whp, and spool just as quickly..

 

You're right. I had just heard from a friend with an FD a while ago that he knew someone who did it with decent results, but I didn't know anything about rx7s at the time.

 

Well, the exhaust ports and manifolds are completely different on both cars, so you'd need a custom exhaust manifold and a custom downpipe. I don't know the specifics of the FC turbo, but I'd guess it's probably not water cooled, so you'd have to do something about the coolant lines running to the stock twins. Obviously, you'd need a custom IC setup and probably need a standalone computer, just for the fact of that it's a different turbo pushing different ammounts of air at different PSI from the stockers. And this is all just spitballing here....

 

This has been done.

You would use a S5 (1989-92) turbo for its fully divided manifold, turbo, and wastegate and at least a compressor upgraded (bigger to4E housing will fit on 3rd gen/cosmo due to closer LIM).

Power potential is 300-400 RWHP, and spool up is about like stock twins in parallel- a bit better or worse depending on compressor/exhaust wheel size and exhaust size.

You would want some sort of computer adjustability as it will change engine VE.

Advantage is less exhaust restriction, lighter weight and simplicity.

You would still have to adapt the oil and water lines to fit up to the 3rd gen locations.

My stock hybrid set up is "p" trim exhaust wheel and shaft, 60-1 hi fi housing/wheel, 60mm external WG (creep was problem).

data logs show boost at 1,300rpm, 2psi at 2,000rpm, 8 psi by 3,000 rpm and full 15 psi at 3,300rpm (4th gear #s).

Spins street tires of cold race tires from 6,000-8000rpm in 4th gear.