has anyone put in a header "DC" ceramic and decided to get a highflow cat
wut size should it be and does it fit both my dc header and stock 5th gen prelude header too
doesn't look like much of a piping size diff between the two
and will i pass smog...damn i live in California

 

you should get the dc dtm catback -

 

Since you live in Cali its gonna be tough to pass emissions without a cat. Id say "gut" meaning unbolt the bolts behind the cat pull the cat down drill out the "honey comb" inside start up your car and use the exhaust to push out the stuff inside the cat. Either that or go to a muffler shop that will hook up with with a straight back exhaust all the way to the stock muffler. Just a couple suggestions.

 

aftermarket highflow cats are terrible i had a random technologys one on my teg and the damn thing just rattled and made all sorts of noise so i just threw on a straight pipe on. www.straightpipes.com is where i got it but you live in cali i wouldnt mess wit it.

 

you better hope you dont get pulled over and fined for the straight pipe

 

hehe i thought so
thnks for the input guys
i guess i shouldn't mess with it then huh?

 

especially if youre in california.
maybe a hi flow cat like carsound or random tech.. but i dont think youll pass smog so if you dont mind chaning it out everytime. also you wont see much improvement unless you get headers intake and exhaust then you will notice a nice gain

 

You won't pick up much with a hi-flow cat unless you are running f/i. I had a random too and they are supposed to be sooo good, but the damn thing rattled like crazy, so I straight piped mine too

 

when ya'll striaght piped it, what you do with the O2 sensors?

my aftermarket hi-flow is makin my checkin engine light come on, says that the cc is bad, but its brand new.

 

i have a random tech high flow cat and mine doesnt rattle one bit....i have no complaints except my exhaust velocity is lower than it should because of the resistance loss by installing the cat......and according to random tech their cats will pass smog in cali if you bought yours from a authorized dealer you will get paperwork that has the carb exemption info in it....

and the check engine light coming on is the ECU sensing the resistance change in the exhaust and that is what is causing the check engine light...its nothing to worrk about....my car throws it about every 300 miles or so....just pull the clock radio fuse 7.5
and it will reset the ECU