My brother just bought a 92 Z28 G92 WITH 83,000 org miles.. Hes doing alot of mods with it... He has dual cats and he wants to takeoff the cats and put a pipe rite threw them... Prob is alot cops around here check under the car if exhaust is loud and give ppl serious fines.. So what he wants to do is put strait pipes where the converters were, and then somehow he wants to put the cats back on and cover the pipes up so they can be so called disguised.. Hes wondering if theres any ways to cover the pipes by putin the cats back on so it seems legal.. thanks guys i need some serious responses

 

Will the car need to be emissions friendly?

 

you could just rip the cats heat shields off and tack weld the shields around the pipes, thats what i did with mine, cant even tell that its not a real cat

 

Will the car need to be emissions friendly?


hehe im a good brother, im a emission inspector in Massachusetts, i dyno get to dyno the cars and pass them, so i can bypass him easily , but thanks so far for the sugges anymore guys thanks

 

How about gutting the cats?

EDIT: Don't gut the cat.

 

isnt puttin pipes on better tho??

 

Yea, it is. I'm just throwing out ideas.

How about adding an electrical cutout AFTER the cats?

 

I gutted my cat and regretted it. Flows like crap and sounds kind of bad too. the heat shield Idea is the best one if you ask me.

 

That's why when someone asks us about gutting the cat, we say to stuff a pipe through it. What you have done is created a chamber in the exhaust and that disrupts exhaust flow and also creates a large "tin/hollow" sound. If you gut a cat, put a straight pipe through it. Plain and simple.

 

you could just rip the cats heat shields off and tack weld the shields around the pipes, thats what i did with mine, cant even tell that its not a real cat



i think were gonna go with this idea.. Does this make it sound nice as well??

 

yes i did it to mine, edelbrock headers into straight pipe plus 3" cat back into 80 flowmaster sounds real nice, probably gonna go with a 40 series later on because i think they sound better

 

yeah i herd 40 series does sound much better, but yeah sounds like a good setup u have there

 

we gutted the cats and man that was a bitch, anyways it sounds aight i guess but my hope is to ripp the cats in half and try to disguise them..

 

gutting the cats makes alot of turbulance in the pipes, and is possibly decreasing the velocity of the exhaust. so you might want to put some pipe through the cats asap.

 

i kno man....... We just gutted them for now... Now we need to get some pipes, its gonna be tuff

 

but yeahs its gonna be tuff

 

since its a dual cat car, keep the cats, they dont rob much power if any, and with them on there, and functional, he has just eliminated the headache of not passin inspection. If he is lookin for capped power, get a cutout. If you go through the trouble of removing the cats, smashing a pipe through and re-installing them, or just putting in straight pipes and making them look like cats, whats to say you dont have an issue down the road that will require them to be existing and functional. I dont believe, and i hate when i have to, do the same job twice.

 

Cats usually rob like 1 or 2 hps at the flywheel for a v6. So for a v8 car, it's robbing 0-0.5 hp at flywheel.

However, putting on performance cats eliminates that loss. And also the fact that your not spewing harmful emission into the atmosphere. ~cough~ ~cough~

I think you should replace the cats w/ some Catco performance cats. It cost like $30-$50 each.

 

Second or third time I've read this from you. I would make it the last, no one needs to know your business and we don't want the feds thinking the board condones it. You don't want to lose your cert.

As suggested above, ram a pipe strait through both cats. Can't see 'em and the cats are still there.

Where are in in MA? They could care less in most of the southeastern area. They would just ticket you for the noise.