LS3 VS LS7 Heads
Team Owner
Joined: May 2007
Posts: 35,248
Likes: 3
From: San Diego Ca
Slightly larger valves:
LS3: 2.16" intake, 1.60" exhaust.
LS7: 2.20" titanium intake, 1.61" sodium filled exhaust
(These might present an issue with piston relief areas, depending on valve lift used, not sure.)
Combustion chamber volume:
LS3: 68.7 cc
LS7: 70cc
The LS3 uses a rectangular shaped intake port that is a bit taller than the LS3's port. This can create some minor flow issues if used with the LS3 intake manifold.
Fit
The bolt patterns and other features should be the same on all LSx engines (I think that is true) but you have to be careful to match intake manifolds, and the slightly larger chamber volume will change your compression ratio just a tad, although not severely, and may also present some flow issues because the combustion chamber will hang over the edges of the bore just a smidgen... probably not a big deal, tho.
Those are the only major differences I'm aware of.
Race Director
Joined: Dec 2006
Posts: 12,358
Likes: 2,893
From: Fort Worth, Texas
Race Director
Joined: Dec 2006
Posts: 12,358
Likes: 2,893
From: Fort Worth, Texas
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