I have heard mixed opinions on this. When searching, most say that it is a good idea, but on MY350Z some are saying that it is not such a good idea. Who has this combo and how has it worked out? Thanks

 

I had the Crawford cats on my car . They flow better than stock cats . I also had RT cats , they flow better than any thing out there . They are very close to running test pipes in flow and noise . The RT's failed on my car and many others . I think they came out with a better cat since then .

Now...as far as power goes . Test pipes and RT cats will produce more power with less boost . Meaning , because they flow better they will not let boost build as much and let the engine breath more and that makes more power .
With the Crawford cats , I had 1.5psi more boost but less power . They dont flow as good , so the motor cant breath as good and produces less power

 

so you are saying they don't flow as well as the RT or they don't flow as well as the stocks

 

They for sure flow MORE then stock . But come up short when it comes to the RT's

 

if it were me i would try to find someone that has a set of rt cats that collapsed and are jsut sitting around. see if they would give them to you or let you have them for a small sum of money and then gut them. thats what i did

 

if you are going to gut them, aren't you better off just buying test pipes? i already have the crawfordz...just wondering if i am better off selling and getting something else

 

gutted rt cats are pretty much test pipes

how bout this i will trade you my gutted rt cats for your crawford cats and you will have a much better flowing system

 

i have my stock gutted cats for sale. they are partially for sale. 40 bucks?

 

the crawford cats work fine, but obviously not as good as test pipes.

I might try test pipes at some point, but not sure. Everyone says they're unbelievably loud with the vortech

do resonated test pipes rasp at all with a vortech and headers/cams/exhaust?

 

i think the vortech is loud with stock cats so i think ill be good with the crawfordz. i don't like the smell from the test pipes...it gets old really quick. id rather smoke some ganj instead of getting high off the fumes from the pipes

 

Must have a exhaust leak . I never smell any thing . Ive ran them all . Stock , RT's , gutted RT's , resonated test pipes ,Crawford , and traight test pipes . The stock and Crawfors are the only ones that didnt have rasp and were a little quieter .

 

I agree with booger, the Crawfords may not produce the best flow but you do get the medium between flow, power and torque plus with the added quietness.

 

ive only heard/see/smelled test pipes on a 350z with an ati procharger and it stunk when i was driving behind it.

 

When I had my vortech I dyno'ed 400hp. Crawford cats, Greddy evo2 exhaust. Alphawerks headers, stock vortech pulley. The car sounded really good.

 

you got 400 rwhp just from those mods?!?!?