So I have a silly question that I'm very unsure about, but can you put an FD upper intake manifold or Cosmo "13B RE" upper intake manifold on a S5 T2 engine? If so what modifications would I have to do?

 

The 3rd gen(FD) manifold has been done. IIRC there are some benefits to it. Requires an adapter of some sort. Search this forum and you'll find the info you seek.

 

Okay, I'll be sure to search the forums. Thanks.

 

Here's a Post showing power gains with an FD manifold

https://www.rx7club.com/2nd-generati.../#post12111835

And heres a post of a type of adapter kit

https://www.rx7club.com/2nd-generati.../#post12111835

Currently I think Obsidian Labs is the only brand available.

 

same link, where is the one with the power gains?

 

Doh! Sorry about that

https://www.rx7club.com/2nd-generati.../#post12052079