No-Cats + Non-Mandrel Bent VS Mandrel Bent.

[xinthenight]

Well, I've noticed a few people at my college that I've seen around town a lot that are driving their old beat up cars without their cats. I'm 99% sure we DO have to have them, so I'm thinking maybe the cops around here just don't pay attention considering how long they've been doing this.

So to get to the point. I may have the chance to make a free full exhaust system(no headers) in the auto shop but it will not be mandrel bent. The thing is...it wouldn't have a cat either. So which would actually give a better performance? No cats and non-mandrel bent(so it will have a little bit of back pressure) or a mandrel bent system with cats?

[SStriker]

Shit your stock exhuast is probly mandrel i know mine was. I would just delete the cats and Muffler if you want a better flowing exhuast.

[9t8z28]

I have witnessed an 8 horsepower gain just from installing mandrel bent pipes coming off of manifolds 3 feet back. Now a complete system is a different story. I have seen gains of 10 to 15 horsepower. Most high flow cats do not rob to much power so you are best doing both.