Originally Posted by Rally_wgn
Hi Jared, thanks for giving the post a read. I guess I am assuming too much in the exhaust section. Most of the Headers sold are either sold with a Cat delete pipe or with high flow cat pipe that replaces you current cat.
Power gains from just a hi flow cat are little or none based on my research so far. Cat back upgrades give decent gains and the header, hi flow combo gives good gains. The two together are your typical full exhaust upgrade.
It is your thread and your choice what to include/exclude, but you give mention to the Borla style headers, which are owned by more people on this board than the EL options, so it would seem like you would present the possibility of HF cat sections as well, since, as you said, hi flow combos in line with headers/cat back give the best gains.