I just unhooked my downpipe from the cat and man is my car faster. Its almost rediculous how much faster it is running open downpipe. Now i am wondering wheather a new HIGH FLOW cat would put any resitriction in the system, or if a resonated test pipe is the best idea.

Second question, im wondering if it is my exhaust that is also too small...2". If i keep it at 2" with a high flow cat, would i see any performance loss compared to open downpipe?

 

bump

 

eh nice to see you repping the b16s! =D cheehoo!

hrmz, yeah you will notice a big difference with no cat... *meow* hah!

on my car i am running 2.25" exhaust... and no cat. just a greddy res. some say a glass pack is nice to keep sound down, but i didnt care, i just ran a 2.25 test pipe, and greddy res. it sounds fine and it pulls a lot harder.

hope this is of any help

peace out

 

alright, how about running high flow cat with 2" exhaust. Too restrictive? or will i even notice

 

2 inch exhaust with no cat sholdnt be too restrictive on a stock B16, i couldnt see you loosing more then 1-3hp vs. a 2.5" system. I run a 2.5" custom bent exhaust on my B16, it has no cat, and no resonator, just a straight through Magnaflow "Wide Open" series Oval muffler. it really isnt that loud, and looks very clean IMO

 

So is a high flow cat going to make any noticable diference loss in power over no cat.

 

with no cat on a stock or bolt ons car you can see anywhere from 2-6 hp gain over having the stock cat on. i'm estimating the numbers to be about 1-4 with a high flow cat over having no cat.. not much of a difference, but once you start making serious power, any cat will be restrictive. that's why people just get a test pipe and save their stock cats for smog time.