Is this correct?
 

If I get a intake.(typhoon) then i was looking to get a free flow cat, then a cat back(borla) but wont i need to change the throttle body and get a bigger one?

I did a quick search for throttle body. See this thread.
https://www.rx8club.com/showthread.p...=throttle+body

Quick answer: Throttle body is big enough