ops

ive seen a few rx7s with single side exhaust,

does the back pressure help at all? id think that if it did mazda would make it single side exhaust stock, so is there any benefit? or is it just some trend or some such?

adrock3217

For one, single exhaust REDUCES backpressure. It allows to exhaust gases to flow out easier, not get all backed up, ala backpressure . And heres the deal. NA needs a certain amount of backpressure, to operate the aux (5th and 6th) ports of the engine. Some people have these either removed, wired open, or electronically enabled, eliminating the need for backpressure. Then you can use whatever you want.

Most people say 2" to 2.5" is as big as you want to go with an NA. Anything higher will only hurt you're performance, and single vs. dual isn't going to make a big difference. To answer you're main question, almost ALL exhaust systems are SINGLE, up until the cat-back. From cat-back to tips, there is a Y-pipe that splits the single pipe into 2 mufflers. The main advantage of a complete SINGLE(no y-pipe) exhaust is less weight. Not to mention less restriction, win-win situation. The only downside to a full single exhaust, is the noise increase. I for one am one of the people who are not affected by extremely loud noises, so exhaust doesn't bother me the slightest bit.

With my Racing Beat Single-to-Y-pipe exhaust system, it was a little bit quiet. Sure, it was loud enough to let people know you had something that wasn't stock, but, it wasn't all that special. And it was heavy! I stress HEAVY! With my now Corksport full single, it is NOTICABLY higher in the decibal levels, but it is much, much lighter.

Sorry for rambling on, I was kind of bored. But anyways, backpressure is only needed for NA's, and if you want you're T2 to spool "mad shift quikz", haha.

88t2romad

covered many times, please do some research on the topic

NZConvertible

This has been discussed to death numerous times before, but the short answer is you're wrong. What matters more than anything is how big the pipes are and how well the system is built. A dual system can cause less backpressure than a single system if it's sized and built right, and vice versa.

The difference is between similarly designed single and dual systems is ~20lb, less that 1% of the car's total weight. The real-world advantage is tiny.

The two most important differences between single and dual systems is cost and looks. You get what you can afford and/or what you think looks best.

ops

i always figured single piping would cause more backpressure seeing as the Y is right after the cats, letting more exhaust flow freely, but i can see how it works the other way around, and ive got an n/a with no engine mods, so i hadnt really planned on changing the exhaust, was just curious