An X pipe is a step up from an H pipe. An H pipe or balance pipe will balance the exhaust pulses evenly between the two pipes, giving a mellower sound.
An X pipe does the same thing but better - that's about all I know. ;laugh
In a 'vette, the best place is just behind the crossmember.
Both give better low end torque and heaps better sound. If getting an X pipe, ask how they make it as a few leave the inside surface eneven with welds etc.
Check this article -
http://www.autospeed.com/A_0608/page1.htmlEDIT: I found this in my travels.
"X-Pipes - Function of an x-pipe is to synchronize the exhaust pulse by merging separate banks together lessening back pressure and increasing scavenging, in result a horsepower and torque increase from 2-10% depending on the application is obtained through out the entire RPM range.
The x-pipe will lower decibel levels 2-3 dbs for a more quality exhaust note.
H-Pipes - Function of a H-Pipe is to equalize pressure between banks in return the vehicle will gain more low and torque and gain in sound quality.
In Race applications the use of a balance pipe is recommended for sound control and extra volume for negative back pressure.
Y-Pipes - Function of a Y-Pipe is used to increase low and mild range torque and horsepower. Y-pipes are used when tight working area's are a factor.";;"1042583502
