Chan93lx50

I was just thinking about this the other day and was wondering why when running dual exhaust do you have an H pipe or and X-pipe?

Why not run two pipes straight from the headers?

What would happen if you did run without and H-Pipe or and X-pipe?

I am assuming you would lose backpressure and with that lose low end HP/Torque. Just my guess!

TheNuge876

The x-pipes are designed at least from what iv'e rad to even out the flow of exhaust pressure and releave back pressure, that would give you MORE power, not less. I dont know how big of a difference it is but that is at least what i believe they are designed to do.

Cmr0z28

Exhaust scavenging.

luckyou03

each exhaust pulse sucks exhaust gases from the opposite side. Without and h or x pipe, they wouldn't exit as fast.

Jameslt1TA

Like said above. For the time being though im not running a h or x pipe. Also a h or x will quiet your exhaust a little and even it out. Mine is very loud and rapsy as it is right now. An h or x is in the future.

Z95m6

It does add hp and tq. I thought i saw in a stang mag that they added an x-pipe to a car that already had a nice flowing dual exhaust and it added like 8rwhp or something.

Jameslt1TA

Dang thats a decent gain i may have to do that as my next mod instead of a down the road one.

canbaufo

I believe the low-mid rpm torque increase is even greater than the hp increase. I remember reading something in one of David Vizard's books that said any type of crossover pipe placed between the collectors and the cats and/or mufflers will almost always yield an approx 10 ft/lb increase in flywheel torque on typical mild street motors. Yes, X-pipes sound very, very good ....I wish I had a true dual setup w/x or h pipe rather than my Borla/E-valve setup, but the Borla setup is pretty nice anyway.

Stoopalini

Here is a great article explaining the details of a tuned exhaus:
http://superchevy.com/technical/engi...t/0505phr_exh/

On a side note, true duals without an X or H pipe can get pretty tiring on long trips. At certain RPMs, the pulsing of the exhaust banks can cause a resonance inside the cab. I had true duals on my blazer and drove from Austin to Sante Fe, and man, it would just drone you out at certain speeds. An H or X pipe would equalize the banks and stop the resonance from happening.

Thomas.

jsetzer

When I had true true duals (flowmaster on each collector, no cross over) it loped a bit harder and sounded a bit meaner.

Added an H in @ where the transmission cross brace is and now it sounds a bit smoother and pulls way harder. Don't have dyno numbers, but with just that change I picked up a couple tenths...