neutron82

but you are only required to have them in a county that does emission testing

eevette2001

As long as you in the UNITED STATES, you're required to have them if they came with the car when it was manufactured. You're just not getting caught if you removed them and your in the US. FEDERAL LAW means the WHOLE COUNTRY.

neutron82

eevette2001

Forgot, Texas is actually Northern Mexico.

neutron82

boo hoo... if you choose to run cats on your car that's totally fine but don't come in here and patronize those of us who choose not to

eevette2001

Why, because it illegal, or because it smells or because it's noisy?

neutron82

because you're annoying and obviously have no real input

Rx7Rob

Neutron don't bother arguing with a troll. Same effect as wrestling a greased pig ...

old stingray

eevette2001

What argument does he have anyway, there is no good reason not to run cats (not even a half a$$ reason not to). It's pure Redneck to run around the street without them.

aaronc7

<----Redneck and proud

neutron82

there is a good reason and if you read as much as you preach you would have seen it in my previous post... go ahead and boost your motor and leave the cats on and have one burn up and lose your motor over it... but never mind all the modding, that voids the stock warranty

REDHOTS

Make zero sense to not run cats. It's not like back in 1975. New Z06/Hellcats, etc. seems to make more power than you could ever most likely use , and running cats. There are more responsible ways to make more power without being part of the problem. If everyone did that, we would all have emission testing mandatory everywhere. A C5 runs greats with cats, stock! I was stationed in the Navy in Long Beach back in 1972, and I didn't know there were mountains around Los Angeles until 3 months later after a big storm cleared the sky. It is definitely a redneck plan to eliminate them.

Midnight

My car is supercharged getting rid of the cats did wonders. But unfortunately I am getting rid of my bullet catback for something quieter. My car has a mild rich tune and i can smell fuel. But that fuel smell is minute compared to all the diesel from big trucks and various autos.

I wouldnt be opposed to running high flow cars but im not spending that kind of bread on cats.

Dave02C5

Gained 14 whp when I punched the cats in my 03 Z. One was half way missing anyway when I pulled the pipes down. Cats are junk power robbers

Mickster144

After reading everyones reply I think I will leave mine off. I had cam, headers and X pipe installed a couple of years ago and yes, the smell is a bit strong in a garage , but most guys actually like it. I was thinking maybe with high flow cats it might sound better..again this is a personal thing. Has anyone actually done this and liked the sound better with the cats. I would love to hear a sound clip of the two, with a cam and headers.

aaronc7

I don't have a true before/after video, but I have videos with the following setups:

-LT/x-pipe w/ high cats, stock ti exhaust, sony action cam mounted to car
-same setup, minus cats, on the dyno recorded on my phone
-new heads/cam (still no cats), dyno on phone
-new setup still, sony action cam mounted to car

You might be able to pick up the individual differences between cats/no cats and cam/before after. Overall the cats give the exhaust a smoother, more refined sound from my experience. Catless it's a bit more harsh, loud. Not a HUGE difference from my experience. Both sound good to me, take your pick.

Mickster144

Thanks for the vids man. Three questions, what brand high flow cats and did you go back to the cats, and did the cats affect the gas smell? Mick

Forcedvert

Oh... and dont take that tag off of your mattress either. I have high flow cats for now, I've heard high hp sc cars can sometimes blow them out. My car is not that high hp... Yet!

aaronc7

I see you're in springfield.... I was born and grew up in Bellefontaine, OH... ha!

Brand wise, I am not sure. Whatever Kooks uses in their X-pipes. Which I believe is a 300 or 400 cell cat, probably a decent quality one. They definitely helped with the smell once up to temp. Cold start you'll still smell it of course, but once it's up and running, no smell. I only had cats with the stock LS6 engine, so with a cam and such you might get some smell, depending on how much overlap your cam has.

I stayed catless and am happy where I'm at. The stock Ti exhaust is quiet, I'll take all the volume I can get. Still nice and quiet just cruising around. Don't mind the smell and there is no emissions checks here in FL.