kevinolivo

im jus wondering whats your guy's thoughts on high flow cats, are there any advantages to having high flow cat vs no cat or vice versa? im about to put an exhaust system on my 98 z28 and wondering what i should do about the cat. any help would be greatly appreciated

hitmanws6

iTrader: (20)

cats will only rob you of 4rwhp. they will kill some rasp, lower your exhaust volume and get rid of the smell of gas you would get from an ORY.

kevinolivo

if i was to keep a cat you think highflow cats would even be worth the money or just leave the stock one on there? will highflow cat still pass smog?

thewholefnshow1

iTrader: (2)

From what I pick up your saying is that your not going to install long tube headers right? If your not I would leave the regular cats on and not worry about the high flow cats or even getting it straight piped. Now if your going with Long Tubes then I would say put hi-flow cats on to get rid of the gas smell and to help keep the rasp down if not none at all and it may make it a tad quieter but it will help bring more of the tone out of the exhaust.

kevinolivo

headers would be the next thing i would do and yea i would go with the long tubes, thanks for your advice man if anyone else readin dis has any input plez post =)

IZRED

If you're getting long tube headers eventually, why are you worried about emissions?

kevinolivo

good point thats wat some of my friends r sayin i guess ill jus make the decision wen i have the money

thewholefnshow1

iTrader: (2)

+1 what he said. But you need to check with your local emissions center. I live in Tennessee and I have a 98 Camaro ss now and it's got LT's, catted Y pipe, cam and yes I passed the emissions test. I guess it depends on how strict they are in your county. I had a 98 T/A with LT, TSP true dual system with gutted cats turned down at the axle and still pass the emissions test. They have a little mirror so they can see under the car, check the gas cap and plug something a scanner into the OBD II. They say as long as you don't have have a SES and have cats on the car you will pass unless your gas cap is jacked up. AN my T/A had 02 sims for the rear 02 sensors and no tune. If that helps.

F-Body_Kustoms

As long as you tune your car, the IM will be a brizze. As long as the ecu think's it has cat's u do Untell they look under your car that is.

thewholefnshow1

iTrader: (2)

Your right but when I first got my LT with my TSP dual system it didn't have cats on it and they said it pass the test but it failed cause it didn't have any cats on it so that when I went back and put the gutted cats on it took it back and passed but here in TN in my county they have a mirror with a hook on the end and they walk around the car and look for them. It's ways around everything you just have to find them. hehe

kevinolivo

thanks for all the input guys im learnin a lot

metalmechanic

i have KOOKS headers and Y pipe w/high flow cats exiting straight out through SLP Dual Dual, no muffler or resonator, sounds great

pheer

iTrader: (3)

is one brand of cat better than another?.... catco seems to be the cheapest, but magnaflow spun seems to be the better....

thewholefnshow1

iTrader: (2)

No not really IMO. A hi-flow cat is a hi-flow cat. But how ever some people get they hi-flow cat that tucks up good or is not that big cause it's kinda tight down there. You know what I mean? That's what I like about the Kooks catted Y I'm on stock mounts but their cats (Magnaflow metallic cats) are very small and fit really good but I can't imagine the clearance on some other cats like the OEM Style big cats on a car with LT's. They may scrape or more than likely hit the bottom of the car.