X-pipe location
07-22-2017, 01:23 AM
#1
Drifting
Thread Starter
X-pipe location
I am piecing together a new exhaust system for my 73. For the sake of routing the pipe I am considering placing the X-pipe under the differential similar to the way a stock exhaust system looks where the two pipes run very close together in that spot. My question is will that erase any performance gains which I would have gotten from the X-pipe by having it so far downstream?
My new system will have long tube headers and 2-1/2" pipes with mufflers at the rear as in a stock set up.
My new system will have long tube headers and 2-1/2" pipes with mufflers at the rear as in a stock set up.
07-22-2017, 06:57 AM
#3
I am piecing together a new exhaust system for my 73. For the sake of routing the pipe I am considering placing the X-pipe under the differential similar to the way a stock exhaust system looks where the two pipes run very close together in that spot. My question is will that erase any performance gains which I would have gotten from the X-pipe by having it so far downstream?
My new system will have long tube headers and 2-1/2" pipes with mufflers at the rear as in a stock set up.
My new system will have long tube headers and 2-1/2" pipes with mufflers at the rear as in a stock set up.
07-22-2017, 07:21 AM
#4
Le Mans Master
That video was great! Putting a X pipe or H pipe on the exhaust reminds me of the intake manifold discussions since on moderately modified motors, aftermarket manifolds, for the most part, add very little power, maybe 5-7 HP on a more aggressive modified motor, less on a mildly modified engine. If you are chasing every last HP/TG, then an X/H pipe for the dollars is worth it.
The real benefit is sound control from the X pipe, mostly. I have neither an X/H pipe on my built 355 L-82 with 2.5 inch duals, Monza turbo mufflers, and 1 7/8 long tube headers...I like the sound as is.
BUT I can tell you this about X pipes: I had the stock 2.5 inch duals with stock ford restrictive mufflers, Stock 4 cat H pipe, and very small OEM primary tubular ford shorty headers on my 1994 Mustang GT 5.0. The sound was less than pleasant. I switched one component at a time on the 5.0: First, magnaflow cat back muffler system, then BBK shorty 1 5/8 inch headers, and last, a maganflow X pipe with 4 high flow cats. The last installation of the X pipe completely transformed the sound of the 5.0 engine. The sound of the exhaust at all RPM's changed with it being much louder (good) at lower RPM's to a tuned, smoother, song at 3,500-6,000 RPM...it really is sweet, guys!
X pipe all the way for sound enhancement! I would skip the H pipe....
The real benefit is sound control from the X pipe, mostly. I have neither an X/H pipe on my built 355 L-82 with 2.5 inch duals, Monza turbo mufflers, and 1 7/8 long tube headers...I like the sound as is.
BUT I can tell you this about X pipes: I had the stock 2.5 inch duals with stock ford restrictive mufflers, Stock 4 cat H pipe, and very small OEM primary tubular ford shorty headers on my 1994 Mustang GT 5.0. The sound was less than pleasant. I switched one component at a time on the 5.0: First, magnaflow cat back muffler system, then BBK shorty 1 5/8 inch headers, and last, a maganflow X pipe with 4 high flow cats. The last installation of the X pipe completely transformed the sound of the 5.0 engine. The sound of the exhaust at all RPM's changed with it being much louder (good) at lower RPM's to a tuned, smoother, song at 3,500-6,000 RPM...it really is sweet, guys!
X pipe all the way for sound enhancement! I would skip the H pipe....
Last edited by jb78L-82; 07-22-2017 at 07:23 AM.
07-22-2017, 09:59 AM
#5
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Packaging is always a problem with Corvettes. However, the farther forward you can put it (most guys put their X pipe right behind the transmission) will at least reduce the flow penalty of cylinders 8&4 and 5&7 that have to deal with the doubled instantaneous exhaust mass flow in the pipes.
I prefer an H-pipe, which can be installed farther forward (I have mine installed right at the header reducers). This exhaust mod is lightweight, makes a noticeable reduction in exhaust noise/drone, and often results in a slight free power increase. No downside to an H pipe.
07-22-2017, 11:23 AM
#7
Safety Car
That would be enough for me :- )
07-22-2017, 12:09 PM
#9
Melting Slicks
I have my X-pipe right behind the transmission. I really like the sound it makes with the chambered mufflers. Much better than without the X.
It has an aggressive snarl or growl to it.
Mike
It has an aggressive snarl or growl to it.
Mike
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jr73 (07-26-2017)
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07-25-2017, 09:52 AM
#13
Team Owner
07-25-2017, 03:56 PM
#15
Melting Slicks
Packaging is always a problem with Corvettes. However, the farther forward you can put it (most guys put their X pipe right behind the transmission) will at least reduce the flow penalty of cylinders 8&4 and 5&7 that have to deal with the doubled instantaneous exhaust mass flow in the pipes.
I prefer an H-pipe, which can be installed farther forward (I have mine installed right at the header reducers). This exhaust mod is lightweight, makes a noticeable reduction in exhaust noise/drone, and often results in a slight free power increase. No downside to an H pipe.
Regarding placement, Pipemax will calculate the theoretical "ideal" location for the crossover pipe, I think on my car it calculated it as "within 21 inches of the header collector" or something like that, but I'm doing this from memory.
Adam
07-26-2017, 11:36 AM
#16
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St. Jude Donor '05
dont get too wrapped up about it though put it where its convenient what a dyno may show youllnever feel with the weight of a car behind it.
07-26-2017, 12:41 PM
#17
Team Owner
This is a great example of a pass under cross member That way you are limited on the tedious routing required by a sorry stock pass through with the hole locations not lined up with header exhausts.
I personally have dual 3 inch with a 4 inch ovalled H pipe maybe 4 inches long. H pipes are more effective the shorter they are. H and X double the exhaust note frequency.
I personally have dual 3 inch with a 4 inch ovalled H pipe maybe 4 inches long. H pipes are more effective the shorter they are. H and X double the exhaust note frequency.
07-26-2017, 12:46 PM
#18
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I think both the H and X pipes only really provide a meaningful power benefit when your performance is limited by your exhaust. -If you went with a slightly undersized diameter for your HP level, the H pipe / X pipe should be more beneficial.
I disagree. As long as Chevy V8s do not not have a 180* firing order, you always have the exhaust pressure/exhaust mass residual issue on cylinders 8&4 and 5&7. An H pipe at the header outlet reduces this problem, regardless of exhaust size.
Regarding placement, Pipemax will calculate the theoretical "ideal" location for the crossover pipe, I think on my car it calculated it as "within 21 inches of the header collector" or something like that, but I'm doing this from memory.
I'm not familiar with Pipemax, but an H pipe at the collector reducer is certainly within 21 inches of the collector. Any further back and you are forcing the double mass exhaust flow to be choked up until it encounters the crossover, whichever form it takes.
Adam
I disagree. As long as Chevy V8s do not not have a 180* firing order, you always have the exhaust pressure/exhaust mass residual issue on cylinders 8&4 and 5&7. An H pipe at the header outlet reduces this problem, regardless of exhaust size.
Regarding placement, Pipemax will calculate the theoretical "ideal" location for the crossover pipe, I think on my car it calculated it as "within 21 inches of the header collector" or something like that, but I'm doing this from memory.
I'm not familiar with Pipemax, but an H pipe at the collector reducer is certainly within 21 inches of the collector. Any further back and you are forcing the double mass exhaust flow to be choked up until it encounters the crossover, whichever form it takes.
Adam
07-26-2017, 01:07 PM
#19
Drifting
Thread Starter
This is great feedback guys. From what I'm reading here I'm probably gonna pt the cross over near the collectors. While I prefer X pipes I think the H pipe looks easier to fit. Sound is important to me though.
07-26-2017, 01:14 PM
#20
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St. Jude Donor '05
Its not a big difference, really
Better using none, you may like it, you can always add later if you want
My car sounded meaner with none at all but its so friggin loud at higher rpm decided toning down some of the high pitch rasp/crackle stuff was in order.
At lower rpm it sounds kind o f muted, not quieter just not as "pronounced" if that helps.
Alwasy fun experimenting...have heard (know how that goes) that the less bends in a system the better.
Better using none, you may like it, you can always add later if you want
My car sounded meaner with none at all but its so friggin loud at higher rpm decided toning down some of the high pitch rasp/crackle stuff was in order.
At lower rpm it sounds kind o f muted, not quieter just not as "pronounced" if that helps.
Alwasy fun experimenting...have heard (know how that goes) that the less bends in a system the better.
Last edited by cv67; 07-26-2017 at 01:28 PM.