Also do dual exhaust, or exhaust that come out on the side(like the lightning) alter perfomance in any way, or is this purely cosmetic? thanks for your help
The muffler is only one part of the exhaust. The rest of the system are the exhaust pipes and tailpipes to also increase exhaust flow.The two combined together will do more than just the muffler will. They make complete kits to replace the entire exhaust system because factory systems are more restricted than the replacement ones.
Side exhaust doesn't really do anything if it's catted and mufflered. I just noticed a shelby mustang with side exhaust.looked stupid. Cars should have exhaust in the back; side exhaust will damage your hearing guaranteed. Dual exhaust doesn't do anything for any four cylinder cars but it can be helpful for reducing backpressure in most v-6+ cars. Usually a full exhaust system (in my belief) is head back meaning it replaces the header(s) cat, and cat back. Stainless exhaust in a bit bigger diameter usually nets decent horsepower and torque, but usually it's all from the replacement of the header and cat with higher flow components and NOT the cat back. Even then, if you go too big you can actually lose horsepower and torque which is never a good thing for something that cost you a lot of money to buy and possibly install.
It depends on if you have a V6/8 for the dual exhaust. If you have a 4 cylinder, don't get dual as it just makes you look like a poser. In fact any in-line style engine should never have dual exhaust in my opinion. As for full exhaust and muffler. A full exhaust typically replaces all of the piping from downpipe back to the muffler. Enlarging the piping gives you free flowing air, and that further improves your hp. A muffler.I'm skeptical if that will make a major difference. Some are more free flowing than you stocker, but not enough to make much of a difference. Sounds cool though! :) as for sound difference between the two it depends really on your engine size and if you remove the resonators. Leave the resonators in if you have anything besides a V8. From my personal experience, it always sounds back. For the most part, a cat-back exhaust system and high-flow muffler is usually pretty standard. Anything more than that is really only advisable when you're building a full out race car and need EVERY once of hp you can get. Anything less than a cat-back system may only show horsepower gains on the butt dyno. ;) Cat back FTW when it comes to sound and performance!
