You fail to understand how an RX-7 works. If I put a cat back on, I'd also have to reconnect my airpump, ACV, and split air pipe. No thanks. Inspections are no problem for me.

 

Lol well seeing how I don't drive an RX-7, I wouldn't know about that. :thumbup:

 

One more thing. When getting new i/e/h/c should i get a new intake manifold? Or is the intake manifold what takes air into the intake valve? Sorry for my lac of knowlegde.

 

No. If you don't know what an intake manifold is, you don't need a new one.

The intake manifold is the big cast aluminum part that the throttle body bolts on to, that bolts on to the head. It is an important performance part... in certain cases.

 

Performance/engine wise, the next big upgrade will be cams, camgears, and timing. Personally, I'd go with suspension mods after i/h/c/e is complete, like springs and shocks or coilovers and braces.