I imagine this has already been covered, but I didn't see it. (I was probably staring straight at it, though)

Anyway, I was wondering, what is the difference between Y, X, and H pipes, other than appearance, obviously. Is it just different sounding exhaust? Or are there performance related differences as well?

Thanks for the help, and sorry if this is just a repost.

 

sound
H is deeper
X is raspier but louder
Y is only on Trans Ams and thos kind of vehicles and i think maybe v6 mustangs?

yea but it is all sound nd they say x's make more power but its barely noticable

 

H is the typical old muscle car sound.
X is a bit higher pitched, more nascar/exotic sound.
Y isn't a cross-over it's taking two headers and combining them to one tube. F-bodies, for example, do this because there isn't enough room to run a full dual exhaust and get decent ground clearance.

Performance wise, X should yield slightly more hp up high (and I mean slightly). H should yield slightly more torque down low (again slightly). This is all dependent on the diameter of the pipes and how smooth the bends are. Smoother/bigger is better.

They are completely a preference thing. I personally love my X pipe's sound but I liked the H pipe sound as well. The X probably yields higher hp numbers since the crossover is at a slighter bend and the air doesn't have to change directions very much (thus it doesn't lose velocity and yields less back pressure).

MAC pro-chamber makes an alternative to an X or H that is a sort of box type cross over, I believe it yields the most noise but I don't think it's any more effective than the other options.