hey, guys... i'm redoing my exhaust system along with a CARSOUND cat. ... but i was just wondering what size i should get...

i now have:

-cheap 4-1 header(outlet is 2" )
-2.25" 5zigen muffler...
...and thinking about getting a carsound cat. ...

do you guys think it'd be OK to go with 2.25" (in/outlet) cat with the header that has 2" outlet? and what about the WHOLE exhaust pipe? what size of piping should i get for a good amount of back pressure for max. HP? any advice would be great...
thanks in advance, guys!!

 

one more Q... kinda newbie Q ... some ppl have 2.25" piping, 2.5" piping(straight)... why is that?

PS. header with 2" outlet... OK or ? if , is there any way to save this header? thanks again...

sorry for my bad English... i don't know how to explain THINGS good...

 

yeah, go with the 2.25 since your muffler is the same. i doesn't make much sense to go to 2.5 unless you plan on upgrading in the near future. the thing with your header, it would be nice to have bigger, but not all people have the money to go around buying parts all the time. you should be fine with what you got for now. not MAXIMUM POWER MAN, but ****, every little helps. stick with one size all the way through. i know the header is smaller, but once it gets through, it'll flow nicely through the exhaust..

 

thanks!! ... yes i'm planning to upgrade... cams, P&P, valve springs, valves, retainers and etc... but i guess i'd have to get bigger header and piping later on...

MAX. HP as in what i can get from what i got...

 

anyone else?

 

ttt

 

nobody?