Making your own car exhaust

>>1156713

When you're cutting it off, avoid sensor lines or anything like that. Make sure it isn't going to drag. Make sure it isn't going to touch anything that it shouldn't. Don't set yourself on fire with any nonsense around the fuel line.

Pretty obvious and simple stuff. You won't see much performance gain on an engine from 3 inch unless you're pumping a lot of air ie. 450+ hp. See the engine masters episode on it. Although there's not much point in not going 3 inch.

Strait pipe it pussy.

>>1156713
Flowmaster makes pipes for those things that are less expensive than buying shit from Napa or wherever you'd buy new pipes. Used to have benders and shit for making exhaust at my work, but stopped doing it because the pre-made pipes got cheap enough thay making them is a waste of time. However, the pre-made ones are shit quality, and sometimes (a lot of times) the flanges and shit are welded on wrong. The flowmaster ones would be better quality, too.

>>1156713
Search some exhaust threads on crownvic.net and pantherbb.com. I've heard that the 16v 4.6 needs some back pressure to run properly with the factory tune, so increasing the diameter of the exhaust may decrease performance. If you just want to fix your exhaust, cut out the bad sections and put in new pipe using U-bolts. If you don't have to pass inspection do the same with the resonators and mufflers to make your land barge sound like a bro dozer.

cars are tuned for a certain exhaust system based on back pressure, so if you just start changing things you might find it running lean.

>>1156720
Straight piping a Grand Marquis is retarded

>>1156713
>but I was thinking about bumping it up to 3" so it could maybe breathe a little better and get better gas mileage

Doesnt work that way, the O2 sensors will recognize it and act accordingly