X pipe vs H pipe

The idea behind the crossover is that you end up with better exhaust scavenging. Exhaust pulses from each cylinder firing cause a pressure wave that moves down the exhaust with velocity. Each pulse has lower pressure ahead and behind it, the theory goes that the low pressure behind each pulse, along with the pulses forward velocity, will "pull" the exhaust gasses following it out of the system. The crossover allows for the pulses to be closer together, so you get better "pull", or, better exhaust gas scavenging. That means a more efficient exhaust and better flow.

That's the theory anyway. The "X" works better for that because it keeps the exhaust gasses at a higher velocity, no need to reflect around a 90 degree corner.

But, the X's are harder to install, the crossover section is longer, so it takes up more space under the car and its harder to find a place to put it. Especially if you're low to the ground and trying to keep the exhaust tucked up high on the floor. Plus they tend to be more expensive. The "H" pipe is quick and easy to install, doesn't take up as much space and can be as simple as a straight piece of pipe.

I run an "X" pipe on my Challenger. I don't think it really sounds all that different from an "H" pipe, both are a little smoother sounding than a dual system without a crossover.

This is an old video of my challenger I took for someone that wanted to know more about my exhaust, its just a generic Summit X pipe I built a system around. Kinda ghetto in the video, its been tucked up a little higher, welded together, and now goes all the way out to the valance. But, it doesn't sound too bad for what's basically a stock 318. Video quality isn't that great, I was trying to get the sound more than anything.

[ame="http://youtu.be/Eamwil-bJBg"]302 Found[/ame]