I wonder why they chose to make the hole inside the tube so small. Is there some benefit in doing so?
exhaust questions
Le Mans Master
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From: Kelowna BC
The mufflers look familiar but can't recall. Borla maybe?
The communication is an H pipe, been used on cars as long as I've had cars. Even my first car, a V8 Monza back in 1980, I got one when I put on duals. Due to the uneven lengths required on the car, a crossover was even more critical. That H in the pic is the factory exhaust.
H and X pipes balance out the exhaust pulses between banks increasing efficiency (power). In general X's have better results (fairly obvious why), but also reduce noise levels a bit.
The communication is an H pipe, been used on cars as long as I've had cars. Even my first car, a V8 Monza back in 1980, I got one when I put on duals. Due to the uneven lengths required on the car, a crossover was even more critical. That H in the pic is the factory exhaust.
H and X pipes balance out the exhaust pulses between banks increasing efficiency (power). In general X's have better results (fairly obvious why), but also reduce noise levels a bit.
Last edited by grantv; May 2, 2016 at 08:33 PM.
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What is showing in the first pic is the stock H-pipe - came that way from the factory. And it does balance out the exhaust flow as stated above.
Le Mans Master
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A stock C5 comes with an H pipe-However the opening between the left and right sides is less than 1/2 inch-----The H pipe you show has a full diameter tube probably 2 1/2 "
This is way better than stock
HOWEVER ---after many years most exhaust companies have found that the LS engine will make just a little more TQ and HP with an X pipe rather than the stock H pipe
An X pipe will give your car more of a race car sounding exhaust--Different from the H pipe that has the traditional low rumble motor boat burble
I love the sound of the X pipe--each to his own taste but as I said on the LS engine the X pipe makes just a little more HP and TQ
This is way better than stock
HOWEVER ---after many years most exhaust companies have found that the LS engine will make just a little more TQ and HP with an X pipe rather than the stock H pipe
An X pipe will give your car more of a race car sounding exhaust--Different from the H pipe that has the traditional low rumble motor boat burble
I love the sound of the X pipe--each to his own taste but as I said on the LS engine the X pipe makes just a little more HP and TQ
Le Mans Master
Joined: Sep 2014
Posts: 5,278
Likes: 539
From: Kelowna BC
A stock C5 comes with an H pipe-However the opening between the left and right sides is less than 1/2 inch-----The H pipe you show has a full diameter tube probably 2 1/2 "
This is way better than stock
HOWEVER ---after many years most exhaust companies have found that the LS engine will make just a little more TQ and HP with an X pipe rather than the stock H pipe
An X pipe will give your car more of a race car sounding exhaust--Different from the H pipe that has the traditional low rumble motor boat burble
I love the sound of the X pipe--each to his own taste but as I said on the LS engine the X pipe makes just a little more HP and TQ
This is way better than stock
HOWEVER ---after many years most exhaust companies have found that the LS engine will make just a little more TQ and HP with an X pipe rather than the stock H pipe
An X pipe will give your car more of a race car sounding exhaust--Different from the H pipe that has the traditional low rumble motor boat burble
I love the sound of the X pipe--each to his own taste but as I said on the LS engine the X pipe makes just a little more HP and TQ
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From: Anthony TX
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St. Jude Donor '08
Attachment 47978028I wonder why they chose to make the hole inside the tube so small. Is there some benefit in doing so?
Can I SWIPE that picture???
Very Telling and I need it for time JUST LIKE THIS! 
GM did that because:
1. Money! Its quick and easy and makes the crossover tube fitment quick and easy.
2. It works for what GM needed it to do so, why make it bigger??
YES,,, It SUCKS and it DID create an issue for GM.. Some C5s experienced a "KEYS JINGLING NOISE" in some RPM Bands.
It was that jagged hole between the two mid pipes that caused the noise and the fix (if you were in warranty) was MID PIPE replacement (CATs and ALL) OR remove the pipes and make the hole bigger and smoother!
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No problem Bill. Well, I got it from Super Chevy, so it isn't really mine to give.
http://www.superchevy.com/how-to/030...formance-info/
http://www.superchevy.com/how-to/030...formance-info/
Last edited by Rob 02; May 3, 2016 at 05:43 PM. Reason: Add link.
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From: Anthony TX
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St. Jude Donor '08
The noise was explained as: The rough cut hole and that hole empting into the larger H pipe section was the cause of the frequency. Most stealerships simply removed the MID pipe, cut out the cross over pipe, made the hole bigger and smother and welded it back together.
Last edited by Bill Curlee; May 3, 2016 at 08:13 PM.
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