I'm relatively new to the Mustang world. I'm picking up my '89 Mustang GT on Tuesday. It has a BBK H-Pipe on it. Now, my question is...what is the difference between X and H pipe and off road and I guess, on road pipes?
the enitre design of both the x and h pipe is to collect the out of sync exhuast pulses and evenly distribute them out the exhaust. h-pipe looks like an h literally just as does the xpipe design. The two have different tones x being a higher raspy sound and the h have a lower grunt to it. Powerwise the xpipe makes a little more power over the h design. On-road means it has street legal emissions catalitic convertors as opposed to the offroad version which doesn't, price wise a catted pipe cost about 3 times as much as a offroad one. Also powerwise again the offroad makes more power over the emissions one.
Another design made by mac is called a prochamber which is a box design that performs the same function as an h and x and makes even more power over the two.
If you take a look at the exhaust pipe underneath, it will look like an H, where as in an X-pipe, the two exhausts come together at a point and then spread apart again to the tail pipes, which creates an X. I believe X-pipes equalize the pressure from both exhausts more efficiently and allow for easier flow, not sure though. As for offroad pipes, that just means there are no cats on it, whereas onroad pipes have them.
lookway back to yestrdays posts thre is one on this with good explanations and theories. I think it is called H pipe loses horse power or close. The actual post is dumb but there are good points inside, it explains it better.