To Cat or Not to Cat

[ar0ck]

Which could possibly be the worse in a 3" exhaust and whats probably your best bet to gain or not sacrafice any power?

Im ordering Edlebrock TES Mid-Length Headers with 3" Y-pipe for Single Cat 94-95 Z28.

But RK Sport has this :
3" Removable Test Pipe
http://www.rksport.com/image?product_id=010949395&size=mid
With this for the next 2 years my inspection is good for, I can run around with it, and when time comes for inspection, toss in the original cat.

My two Ideas is :
1. Get a High-Flow cat welded in permenently
2. Test Pipe & swap in the original cat for inspection
3. Gut the catalytic converter.

[foff667]

just get a test pipe either welded in or get some flanges put on similar to the pic...i like the flange idea so long as the bolts dont rust in 2 years and youd need to cut them off anywayz :roll:

[HardcoreZ28]

Put a cat on it so you don't have to worry about changing all the time. Then have a cut-out installed before the cat so you can open it up completely whenever you want.

[The Fixer]

:werd: If you get a RandomTech or other name-brand high-flow cat, you won't lose more than 1 or 2hp anyway. If it were me, I'd keep it smog-legal all the time. You never know where one of those roadside DMV checks are gonna pop up! And if they stick the mirror under your car and see a testpipe, you'll be walking home.

[89 Trans Am WS6]

Yeah dude, im going high flow cat on my car..

Its just not worth the risk of getting caught without a cat, besides its not any kind of noticeable gain w/o one comparted to high flow. I gutted it on my 89 and didnt feel a thing..:( then i replaced it all together witha cutout..just louder..id say keep it smog legal bro

[NJSPEEDER]

i say go no cat.
i ran with no cats on my 91 for almost the whole time i owned it and never had a cop say a word to me. and that was with TES headers, !cat, and a borla cat back with teh open plate.

later
tim

[IROCZBeast]

i don't think gutting the cat would help u for inspection cause i think they have something that actually tests for fumes.

[ar0ck]

I forgot about the spot inspections. Although I never had the problem with them yet, Im still paranoid. Im going to go with a high-flow cat.

[Oddball]

You live in Jersey. Cats are mandatory if you drive on the street. Don't be a douche. Most high-flo cats wont lose that much horsepower.

[1RawTA]

Cats really dont gain to much power on a bolt on car.. maybe 4rwhp. i personally dont think it is worth the fine and hastle, thats why my car still has them on. just get a good highflow cat and you will be set

[NJSPEEDER]

Most high-flo cats wont lose that much horsepower.

cats cost a ton of power and let off gases that are more toxic than the ones they are designed to prevent.
on little g's v6 teh !cat was worth a full mph of trap speed, and that is on a V6. on my 91 rs i gained about 1.5 mph of trap speed when i went with a delete pipe with a 305 tbi.
also the difference between a "high flow" cat and a regular one the same size does not make them worth anything at all. almost every "high flow" design on the market flows only 10-15% more than a stocker.

later
tim

[JL8Jeff]

Yeah, but an aftermarket high flow cat will only cost about 3-5 hp at the most. And that was testing done on a 455 Pontiac in a 67 Firebird that ran low 11's I think. Basically put, get a high flow cat(s) and stay legal. The fine for not having a cat is a heck of a lot more expensive than the cost of the high flow cat.

[NJSPEEDER]

i would be interested in seeing how they did that test. i took a high flow cat off of my car and gained a ton. the cat was still in good shape, not melted or clogged or anything.
it is a major restriction and i have never even heard of someone getting fined for not having one. you know if it happened it would be all over every board that day.

later
tim