Hey just want to start off by saying yes i did search, and yes i did find like three pages of stuff, but nothing that matched my setup so i just want to post and double check before i go out and spend the money. I have a greddy evo2 catback on order, and am waiting for it to get here. Now im also going with a Greddy 4-2-1 ss header. I believe the header collector size is what 2" and the evo2 is 2.36? So what size would i need for a high flow cat? What inlet size and outlet size, and how long should it be? Oh and how many flanges if any and do i need the o2 bung? Thanks guys. I'm so excited to have this finally done...and oh btw im driving a 95 ls...

 

not shure, but you can take the cat back and the hi flow cat and have a muffler shop put it together for you. thay and weld flanges on and fit it all perfict. but a muffler shop wont instal a header.

 

bump...i would really like to order it today if anyone has any info. I would greatly appreciate it

 

does anyone have a for sure answer? I would really like to order this asap