cat vs test pipe?

[SixSquared]

k here's the deal... the high flow cat I have is NOT matching up to my header. I have the opportunity to get a ceramic coated SMSP test pipe, which DOES fit... is there that much of a power difference? I don't want my car to be ridiculously loud, but if there's a decent power difference I could be talked into it. I'm also eventually planning to boost this motor, so give me some advice guys.

BTW - I have a B18c1 with intake/header done as well as some other little things here and there, if that counts for anything.

[MDPsJcars]

I dont have any actual dyno numbers for you but.... I run a bolt in straight pipe on my b16 except for about week around emissions time every year. Then i put in a high flow cat. I will tell you that it is considerably louder and raspier with the straight pipe. However i am in a hurry to get it back on there every year because there is a noticeable difference in top end pull... like 7k and up. With the cat on there the powerband seems to flatten out up top, and with no cat it keeps pulling harder. Pulls harder on the butt dyno anyway.

[BigPoppaHurtm]

Most people with test pipes will agree that there is a big difference in the butt dyno with 'em. I dont have one on my car yet but from what Ive heard many s2000 owners with test pipes (some who are supercharged) pass emissions without cats. Thats not an exageration. If your test pipe will be custom made ask them to make mounts to keep your cat heatshield in place so it looks like the cat is still there in order to fool the emissions people. Good luck.

[KevinT707]

Save the environment, use the cat. I have one & I still make power

[crhatchzc]

when i had my hatch i didnt have a test pipe on there but with it on or off i really didnt feel much of a diffrence so i would say leave it on and plus after awhile it started to get really really annoying with it off

[§treet_§peed]

i gotta high flow cat along with headers. 2.5 cat back, cold air intake, on my D16Y7 does great for what it is. i've heard like there saying though that it does do wonders with a test pipe..but o well. new exhaust will have to be made when i swap...as far as emmisions go, i don't have to worry about them, lol ..when you look at my highflow cat, there's nothing on the inseide btw...

[Black R]

.....it really depends on the cat.

there are some good high-flow cats - like the renault cat used by hytech, which have virtually no power losses compared to a test pipe.

however, the majority of the cats on the market will sacrifice ~5whp or so - even more if you're making over 200whp.

that being said, the tone isn't too noticably different - maybe a few decibels.

and you can't pass emissions sniffer with a test pipe.

[1439/2000]

If you have a stock Honda with an intake and header you won't gain shit from taking out your cat. Just leave it.

[SixSquared]

well the stock cats are long gone.. both the GSR one and the stock D series one that actually came on the car. The reason I ask is because for about the same price, I can get either a new high flow cat OR the test pipe... Doesn't really matter too much either way to me... Like I said, for right now, it's stock with a bolt on here and there.. eventually I'm gonna be looking to boost it, but the whole thing needs to be rebuilt first. I'm in Athens, so we have no emissions.. that's not a concern. The high flow cat that I bought doesn't fit the header piping (too small) and the bolt holes don't line up. So basically I'd either be getting this test pipe or another high flow cat that does fit. Just looking for pros and cons to each.