1 cat??

[Jonny Cash]

Im going to get some advanced technology high flow cats today.I need to pass inspection,and quiet the my car a little bit. This is probably a stupid question,but Im going for it anyway. Do you guys think I could do 1 cat??
I was looking at my friends GTP yesterday and his exhaust setup is similar. He has only 1 cat welded right before the Y on full 3". Has anybody ever done this before?? Are the results not as good? If not then why not?

 

[Mr Anonymous]

To pass inspection (presuming your state requires a visual inspection to confirm cats are present) it's usually easier just to swap in a stock pipe for the inspection. And with the cams you've got, if you have to pass emissions too you're going to want to have both cats on there to give you a chance of passing.

Some people have looked at a single cat, but I'm not aware that anyone has done it. My concern would be being able to get the cat close enough to the manifolds that the exhaust gasses would stay hot enough to actually start and maintain the catalytic process.

 

[SASHO91]

I have a thread about this somewere.....
From what i gatherd, it was a bad idea... because the cat would be too far back from the exh. mani. that it would function properly... the cat(s) have to be hot in order to "work"...
yeah i though of that.... trying to come up with another y-pipe design.... didnt go through though....
if you do decide to do it.. let us know though....

 

[Jonny Cash]

To pass inspection (presuming your state requires a visual inspection to confirm cats are present) it's usually easier just to swap in a stock pipe for the inspection. And with the cams you've got, if you have to pass emissions too you're going to want to have both cats on there to give you a chance of passing.

Some people have looked at a single cat, but I'm not aware that anyone has done it. My concern would be being able to get the cat close enough to the manifolds that the exhaust gasses would stay hot enough to actually start and maintain the catalytic process.

Yea, as far as inspection goes. You know as well as anyone I probably wont pass just with a different y-pipe.So right there a different pipe is pointless.Besides all that, Im more or less trying to make the car a little more streetable, and more quiet. I dont think Ill lose alot of power if none at all. Even though its a weekend car I still the think no cats is a little too loud . Im probably going to get 2, and just do it right.

 

[SeanMc]

If you are in California, you'll want to stick with the 2 cat setup.

 

[Jonny Cash]

If you are in California, you'll want to stick with the 2 cat setup.

Hmm.. Ive never heard of providence California. :laugh_ti: JK. I know theyre strict over there.

 

[SHOZ123]

Im going to get some advanced technology high flow cats today.I need to pass inspection,and quiet the my car a little bit. This is probably a stupid question,but Im going for it anyway. Do you guys think I could do 1 cat??
I was looking at my friends GTP yesterday and his exhaust setup is similar. He has only 1 cat welded right before the Y on full 3". Has anybody ever done this before?? Are the results not as good? If not then why not?

I would think the GEN 3 third cat would bolt right up to the Y pipe.

 

[Mels]

Hey Mr. Ca$h,

I don't know whether the 3.0 and 3.2 y-pipes are interchangeable, or if you'd even consider this option, but if it's a hurry you're in and can't wait for a new replacement to be delivered I could give my Midwest unit to you with the understanding that you'll order a replacement Midwest unit right away.

My Midwest pipe is new, uninstalled and waiting patiently in the attic.

Give me a call if interested, you SHOuld still have my number.

Mels

 

[Mr Anonymous]

Yea, as far as inspection goes. You know as well as anyone I probably wont pass just with a different y-pipe.So right there a different pipe is pointless.Besides all that, Im more or less trying to make the car a little more streetable, and more quiet. I dont think Ill lose alot of power if none at all. Even though its a weekend car I still the think no cats is a little too loud . Im probably going to get 2, and just do it right.

A stock y-pipe (or aftermarket w/cats), as long as the cats are intact and not destroyed will lower your emissions a good amount over the catless setup. Maybe not enough to actually pass the emissions test, but even a brand new pipe might not help it pass. You'll probably need to pull the spout and do some other tricks to get it to just squeak in under the limits.

FWIW, your loudness has more to do with the lack of a resonator than with the lack of cats. The catless pipe contributes more rasp to the equasion, but a 18"-24" long resonator would do wonders to quiet it down for you.

 

[Jonny Cash]

A stock y-pipe (or aftermarket w/cats), as long as the cats are intact and not destroyed will lower your emissions a good amount over the catless setup. Maybe not enough to actually pass the emissions test, but even a brand new pipe might not help it pass. You'll probably need to pull the spout and do some other tricks to get it to just squeak in under the limits.

FWIW, your loudness has more to do with the lack of a resonator than with the lack of cats. The catless pipe contributes more rasp to the equasion, but a 18"-24" long resonator would do wonders to quiet it down for you.

Thanks for the info. I wouldnt want to get a resonator because that has to be the ultimate restriction. Im still undecided whether I want to get cats or not. Im definitly not go out and buy a new Y-pipe. And thanks again Mel for your help. It seems like every time I have a problem your always there to help. I really appreciate it.
Thanks, Jay

 

[operdot]

adding small amounts of acetone to the gas reduces emissions ENNOURMOUSLY and it helps gas mileage too, research it it really works , as far as one cat setup goes well I would think it would be better for performance and when I bought mine for they gave me a guarantee that it will pass emissions or my money back. And the one I got was a 2.5" in/out magnaflow hi-flow cat designed for a chevy V8.

 

[Mels]

And thanks again Mel for your help.

You're welcome Jay.

If I could get the new pipe onto my car this weekend I'd give you the stocker. Probably not what you'd want on your car all the time, but for inspection it'd be handy to have...

The problem as you know is that I'm kinda restricted to this recliner and wouldn't be able to climb around all the "treasures" in my garage to get to the tools to swap these pipes out.

Sorry I can't help more immediately.

Check your PM, I know where a factory one is sitting in someone else's way...