C6 vs. C5 exhaust
Thread Starter
Safety Car
Joined: Jun 2003
Posts: 4,469
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From: Rockville Centre NY
C6 vs. C5 exhaust
Some observations looking at the C5 and C6 stock exhaust systems now in my attic:
- C6 exhaust manifolds are much shorter. I guess that was to get the catalytic convertors closer for quicker warmup, but I'm sure they must flow better as well.
- No "pup" convertors on C6, that's got to help flow.
- Overall less sharp bends in entire C6 system.
- Much more straight thru muffler design on C6.
- Very light H pipe on C6.
- C6 mufflers actually weigh less than Corsa Sports I replaced 'em with. So maybe you gain a few HP, but you give some of it back in increased weight. Conversely, C5 mufflers weigh more than the Borla Stingers I replaced 'em with.
So, GM seems to have produced an awfully good stock exhaust system on the C6 compared to the C5. Still for me the sound alone of Kooks headers and Corsa Sports was worth changing from the stock C6, along with 25 RWHP (which will go up once we can tune!).
- C6 exhaust manifolds are much shorter. I guess that was to get the catalytic convertors closer for quicker warmup, but I'm sure they must flow better as well.
- No "pup" convertors on C6, that's got to help flow.
- Overall less sharp bends in entire C6 system.
- Much more straight thru muffler design on C6.
- Very light H pipe on C6.
- C6 mufflers actually weigh less than Corsa Sports I replaced 'em with. So maybe you gain a few HP, but you give some of it back in increased weight. Conversely, C5 mufflers weigh more than the Borla Stingers I replaced 'em with.
So, GM seems to have produced an awfully good stock exhaust system on the C6 compared to the C5. Still for me the sound alone of Kooks headers and Corsa Sports was worth changing from the stock C6, along with 25 RWHP (which will go up once we can tune!).
Thread Starter
Safety Car
Joined: Jun 2003
Posts: 4,469
Likes: 20
From: Rockville Centre NY
I actually would have preferred going with Borla again for my C6, but, being the impatient modaholic I am, went with Corsa to have single tips (only dual tips were available on Borla). Wanted the tips to look different than the stock dual tips.
I have trouble believing the C6 stock mufflers bottle up 15 RWHP. So you only gain 10 more RWHP by going with long tube headers/x-pipe/hi-flow cats? Something doesn't smell right. Kinda like the intake that supposedly makes 40HP on a C6.
I have trouble believing the C6 stock mufflers bottle up 15 RWHP. So you only gain 10 more RWHP by going with long tube headers/x-pipe/hi-flow cats? Something doesn't smell right. Kinda like the intake that supposedly makes 40HP on a C6.
Premium Supporting Vendor
Joined: Jul 2002
Posts: 418
Likes: 53
From: Oxnard CA
Originally Posted by c5grandsport
I actually would have preferred going with Borla again for my C6, but, being the impatient modaholic I am, went with Corsa to have single tips (only dual tips were available on Borla). Wanted the tips to look different than the stock dual tips.
I have trouble believing the C6 stock mufflers bottle up 15 RWHP. So you only gain 10 more RWHP by going with long tube headers/x-pipe/hi-flow cats? Something doesn't smell right. Kinda like the intake that supposedly makes 40HP on a C6.
I have trouble believing the C6 stock mufflers bottle up 15 RWHP. So you only gain 10 more RWHP by going with long tube headers/x-pipe/hi-flow cats? Something doesn't smell right. Kinda like the intake that supposedly makes 40HP on a C6.
Instructor
Joined: Jul 2004
Posts: 115
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Originally Posted by David Borla
The Borla S-Type system for the C6 is 14 lbs lighter than stock and we experienced a 10hp to 15hp gain.
Thanks,
PvK
Premium Supporting Vendor
Joined: Jul 2002
Posts: 418
Likes: 53
From: Oxnard CA
Originally Posted by Peter von Kleist
David, are your X pipes ready for shipment? I have ordered the exhaust and X-pipe and am looking forward to having them installed.
Thanks,
PvK
Thanks,
PvK
The quiet/less aggressive cat-backs are almost ready.
Le Mans Master
Joined: Nov 1999
Posts: 7,695
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From: Imperial Beach CA
Originally Posted by David Borla
I'm fairly certain (and you'd have to ask LG Motorsports to know for sure) that the LG long tubes in conjunction with the Borla Cat-back setup will get you over 30hp on a C6. Again, we'll have to check with LG.
Thread Starter
Safety Car
Joined: Jun 2003
Posts: 4,469
Likes: 20
From: Rockville Centre NY
Originally Posted by David Borla
I'm fairly certain (and you'd have to ask LG Motorsports to know for sure) that the LG long tubes in conjunction with the Borla Cat-back setup will get you over 30hp on a C6. Again, we'll have to check with LG.
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Premium Supporting Vendor
Joined: Jul 2002
Posts: 418
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From: Oxnard CA
Originally Posted by c5grandsport
O.K., so let's agree you get somewhere around 25-30 RWHP from doing headers/x-pipe/hi flow cats/cat-back exhaust on a C6 without tuning. How much can we honestly attribute to just the cat-back exhaust, 5 RWHP? I'm still not buying the C6 stock mufflers bottle up 15 RWHP (the C5 yes, the C6 no).
The stock system flows very nicely, but it does "bottle up 15 RWHP". Considering the perameters they have to work within, this actually says a lot for the GM exhaust engineers. They built a fine exhaust.........
Thread Starter
Safety Car
Joined: Jun 2003
Posts: 4,469
Likes: 20
From: Rockville Centre NY
Still can't see how you get the same gains on a C6 with just a cat-back as on a C5. The C6 stock system seems so much better. But soundwise, I gotta admit there's nothing like the low rumble of those Borla Stingers on my C5 with headers, heads and cam. May have to rip the Corsa Sports off my C6 once the single tips are available from Borla!
