Stock 'H' Pipe vs 'X' Pipe??
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From: St. Louis MO
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Re: Stock 'H' Pipe vs 'X' Pipe?? (l2vette)
I don't know about performance improvement but I added the Bassain X after listening to others. It made a big difference in the sound with the Corsa Indy's.
For those interested here is a link to my X-Pipe install... http://home.att.net/~jansseng/x-Pipe.htm
For those interested here is a link to my X-Pipe install... http://home.att.net/~jansseng/x-Pipe.htm
Safety Car
Joined: Feb 2001
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From: Greenville NC
Re: Stock 'H' Pipe vs 'X' Pipe?? (RG in Dallas)
97 and 01 inside opening on the factory h-pipe appraches 2". The 98,99 and 00 are only about 1/2" at best.
Le Mans Master
Joined: Aug 2000
Posts: 5,529
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From: Austin Texas
Re: Stock 'H' Pipe vs 'X' Pipe?? (ncvetteman)
The real difference between an H-pipe and an X-pipe is that the H-pipe has a high frequency/RPM cut-off that the X-pipe does not.
A GM V8 has a firing order of LRLLRLRR. This is decidely imbalanced, and causes the need for an H-pipe or X-pipe. The doubled up LL and RR firing pulses are the cause of the idle burble and cause irregularities in the exhaust pulses traveling down the exhaust manifold/header. An H-pipe is an inexpensive means to allow the doubled up LL and RR pulses to use the "other" exhaust system. But since there is a 90 degree angle from the exhaust through the tube, above a certain exhaust velocity, the pulse has trouble turning the entrance corner and turning the exit corner on the H-pipe. Therefore, the H-pipe looks like it is connecting the R and L exhayst systems below a certain RPM, and above that RPM it looks like the H-pipe is not there at all.
The X-pipe does not have this rpm cut-off and works over the entire rev range. In addition, in an X-pipe system, not only are the exhaust pulses re-balanced, but they have equal access to either exhaust outlet, and the flow tends to separate and travel down both exhausts--thereby--finding a lower resistance, which in turn promotes lower back pressure.
A GM V8 has a firing order of LRLLRLRR. This is decidely imbalanced, and causes the need for an H-pipe or X-pipe. The doubled up LL and RR firing pulses are the cause of the idle burble and cause irregularities in the exhaust pulses traveling down the exhaust manifold/header. An H-pipe is an inexpensive means to allow the doubled up LL and RR pulses to use the "other" exhaust system. But since there is a 90 degree angle from the exhaust through the tube, above a certain exhaust velocity, the pulse has trouble turning the entrance corner and turning the exit corner on the H-pipe. Therefore, the H-pipe looks like it is connecting the R and L exhayst systems below a certain RPM, and above that RPM it looks like the H-pipe is not there at all.
The X-pipe does not have this rpm cut-off and works over the entire rev range. In addition, in an X-pipe system, not only are the exhaust pulses re-balanced, but they have equal access to either exhaust outlet, and the flow tends to separate and travel down both exhausts--thereby--finding a lower resistance, which in turn promotes lower back pressure.
Safety Car
Joined: Oct 2000
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From: Monticello MN
Re: Stock 'H' Pipe vs 'X' Pipe?? (ModifiedC5)
I thought I recall some folks leaving in the factory H-pipe and adding an x-pipe?
Ed
Intermediate
Joined: Jan 2000
Posts: 39
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From: North Hills, Ca
Re: Stock 'H' Pipe vs 'X' Pipe?? (C5XTASY)
My 97 had the large diameter H pipe. I replaced it with the X pipe for the sound. I didn't expect any gain in power. Put the X pipe on and the sound is MUCH cleaner. No more motor boat gurgling sound on decel and just sounds very healthy at all rpm's. I didn't notice an increase in power though. I'm assuming there was, but probably not much.
Pro
Joined: Jun 2001
Posts: 605
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From: Summerville SC
Re: Stock 'H' Pipe vs 'X' Pipe?? (RG in Dallas)
RG, do you know how big the holes are in the "X" on the 2 you have pictures of? how about others? it seems to me a 2" hole in an "H" pipe would be better than a 1" hole in an "X" pipe. Are the holes also bigger, I guess is my question? :crazy:
