LS7 exhaust on LS3 engine
Le Mans Master
Joined: Mar 2001
Posts: 8,417
Likes: 3,904
From: Omaha
2020 Corvette of the Year Finalist (performance mods)
C4 of Year Winner (performance mods) 2019
No, it should not. You can install them without retuning and pick up about 14-15RWHP. The issue that most modifications will run afoul of is the retuning of the ECM. GM will typically require verification of stock tune from the service department before signing off on major warranty work.
Race Director
Joined: Oct 2005
Posts: 14,999
Likes: 200
From: Bay Area Ca.
BECAUSE MOST WILL ADD A TUNE WITH THE EXCHANGE OF EXHAUST SYSTEMS.
IT IS THE TUNE THAT WILL VOID WARRANTY.
IT IS 3 INCH PIPE AS THE STOCK LS3 IS 2 1/2 INCH.
I suppose some will just do the switch without the tune, I did not!
IT IS THE TUNE THAT WILL VOID WARRANTY.
IT IS 3 INCH PIPE AS THE STOCK LS3 IS 2 1/2 INCH.
I suppose some will just do the switch without the tune, I did not!
Le Mans Master
Joined: Mar 2001
Posts: 8,417
Likes: 3,904
From: Omaha
2020 Corvette of the Year Finalist (performance mods)
C4 of Year Winner (performance mods) 2019
Race Director
Joined: Oct 2005
Posts: 14,999
Likes: 200
From: Bay Area Ca.
From my viewpoint with increasing the exhaust flow this much a tune would be nice. Necessary maybe not but is reasonable thing to do . There is hp to be made with a tune. More than the manifolds in my experience.
Yes there is the warranty problem, btw I had a tune on my new 08 within the first 1,000 miles. Picked up 24 rwhp and 17 rwtq. This was on a wheel off dyno.
AND headers is the way to go but alas I live in California and took them off and installed the Z06 stuff.
Picking up the xtra hp is cool but I wonder what your A/f is without a tune.
Yes there is the warranty problem, btw I had a tune on my new 08 within the first 1,000 miles. Picked up 24 rwhp and 17 rwtq. This was on a wheel off dyno.
AND headers is the way to go but alas I live in California and took them off and installed the Z06 stuff.
Picking up the xtra hp is cool but I wonder what your A/f is without a tune.
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Le Mans Master
Joined: Mar 2001
Posts: 8,417
Likes: 3,904
From: Omaha
2020 Corvette of the Year Finalist (performance mods)
C4 of Year Winner (performance mods) 2019
Sorry, no A/F on those runs, but I ran the car for a year in that configuration with no codes or issues.
Instructor
Joined: Nov 2013
Posts: 104
Likes: 1
From: Provo UT
It's worth doing if you can get the manifolds back full exhaust for cheap, maybe at the beginning of the season when the Z guys are getting long tubes, and if you can do the work yourself. If you have to get them shipped to you and then installed at a shop then you won't save much over long tubes anyway.
I was going to do the LS7 exhaust and then did the math and decided not to.
I was going to do the LS7 exhaust and then did the math and decided not to.
