Exhaust

[white GTP]

Hello everyone, I have a '94 GTP with a 3.4 DOHC. I had the car at my tech shop for some repairs thermostat and coolant. The car was up in the air and my friend comes over to me and asks why in the hell I have a cat converter on my car if i dont need emissions. He told me to bring the car over to his house and he will chop off the cat and the resinator for a low cost and weld everything back into place. I already have flowmaster 40 series on the car already and it sounds ok except for around 2500 rpms when this stupid rattling noise kicks in. I just though I would ask everyone if this would be a good idea of just a waste of time.

Thanks much for reply's

[audioimagez]

Your friend is a moron. If you want more flow get a hiflow cat. Otherwise leave it on.

[ShinyHappyGP]

Removing the cat may cause drivability problems as the car is computer controlled to run with it. Also, in most states, cars much older than '94 do need emissions testing and if they don't now that can change too. As "audioimagez" says, go with hi-flow cats.

[The Burning Rom]

.....a high flow cat would flow WORSE than having no cat at all! The converter catalyzes the exhaust before sending it into the atmosphere. Basically, it just cleans it up a bit. In my opinion, they are somewhat useless (at least around here), and they can be a fire hazard. I've seen them get so hot that they glow red...which can be a fire hazard if the car is driven in taller grass.

If there is no oxygen sensor BEHIND the converter, then removing it will NOT cause ANY driveability problems..as far as the computer is concerned. Neither my TGP nor my GT have converters. And I have no problems with either car.

As for emissions laws if you city doesn't test it every year or two when you renew the plates then you don't have to worry about it. If a law is ever introduced, I would almost bet any car built or modified before the law is passed (that isn't under emissions warranty anymore) will be grandfathered.

[ShinyHappyGP]

Sorry, but the excess emissions from your cars without cats do end up sending pollutants elsewhere. Since when is keeping the air everyone breathes useless? Responsible modifications are the only way to keep it credible and keep excess restrictions from becoming law.
Older cars are not always grandfathered in and with pollution getting worse, I wouldn't count on it. In fact, all laws enacted thus far cover the vehicle the way it was manufactured and expressly do not include modifications - so if you take them off and then emissions inspections are introduced, your car will not pass an inspection unless you put them back on.
Cats only glow red when they are not functioning properly and if you can't tell when they are affecting your cars performance, then you don't belong driving any kind of performance vehicle. Ditto if you don't take care of and maintain them properly. As for the taller grass, most states have paved roads and since these are not off road vehicles, they shouldn't be driven on tall grass too often.
Removing any emissions equipment, of which the cat is, can affect drivability, but not always. If the car is under warranty, it will void it. Either way, it is illegal and irresponsible.

[The Burning Rom]

Originally Posted by ShinyHappyGP

it is illegal and irresponsible.

That's your opinion. I'm entitled to my own.

Here in WI we don't have too many problems with emissions. There isn't a pile of cars everywhere you look. You can tear around with no exhaust at all and not get bothered by anyone. And some of us don't drive our high performance machines on pavement all the time. There's actually grass out here....there isn't pavement everywhere you wanna go. I chose to remove my converters because I don't drive my cars much, and when I do...I don't want that chunk of metal slowing me down or potentially causing problems. The car I drive everyday has a converter. When it becomes a problem..it will no longer have a converter.

[JJUBECK]

Such hostility in this thread......If you live in a state that doesnt do emission test then the best thing to do if to cut it off less resistance more airflow. However, if you do live in a state that does do emission testing then either get your cat punched out or the high flow cat should do the trick. You also might want to add a cutoff to your exhuast. It will make you exhuast pretty damn loud and no resistence from your mufflers.

[GTPJeff]

Not running a catalitic converter, verses running a high flow cat.. The car with NO converter will make less lowend torque, and no more power on the topend..

If a converter gets cherry red, it's because your car is running excessively rich.. The more fuel you dump, the hotter they get.. That's the catalitic action that takes place..

Punching out converters are the worst for making power... You'd do better by welding a converter shell around a piece of straight pipe..