2.5in collector in from the header and can go to fit a 2 and 1/4 in. exhaust out? or 2.5in on both sides?

 

~2.5" both sides...... you need to modify the B-pipe.

 

who sells carsound cats online

 

sig.

 

how does that work? would i be able to run a say..n1 or greddy sp catback system or no?

 

the n1 yes...greddy probably...not sure

 

Check out this thread: https://honda-tech.com/zerothread?id=76912

You can buy a CarSound cat that's pre-flanged and will directly bolt up to your header and your cat-back exhaust -- no matter which brand. They all use the same spec flanges, or else none of them would bolt up the same.

 

but im saying using this w/ a jdm 4-1 header w/2.5in. collector.....the carsound cat. has a 2.5inch in and a 2.5 inch out? how would that work out on a say...60mm catback?? they aren't the same sizes. sooo im confused and wondering how to set this up? along with wat catback system...and no i don't wanna run a testpipe....