Gen III heads on LS2
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Gen III heads on LS2
I was thinking it could be interesting/economical to use ported LS1, or better, LS6 heads, and bolt them on the LS2. Since they are designed/cast for the smaller 3.9 bore.
For really easy higher compression the ported 5.3 truck heads would be a thought since they are virtually the same as the LS1 heads, just smaller chambers.
Just preliminary thoughts, since heads cast with smaller chambers are better then milling heads for compression. Hence the success of using 5.3 heads on LS1's.
I think a ported LS6 on the LS2 would be super. At least early on until the aftermarket porting ability on LS2's overcomes the bennefit of the current ported LS6 castings with the bennefit of smaller chambers on the LS2 4 inch bore.
[Modified by kewlbrz, 6:35 PM 6/22/2004]
For really easy higher compression the ported 5.3 truck heads would be a thought since they are virtually the same as the LS1 heads, just smaller chambers.
Just preliminary thoughts, since heads cast with smaller chambers are better then milling heads for compression. Hence the success of using 5.3 heads on LS1's.
I think a ported LS6 on the LS2 would be super. At least early on until the aftermarket porting ability on LS2's overcomes the bennefit of the current ported LS6 castings with the bennefit of smaller chambers on the LS2 4 inch bore.
[Modified by kewlbrz, 6:35 PM 6/22/2004]
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St. Jude Donor '15
Re: Gen III heads on LS2 (kewlbrz)
They LS2 head part numbers where posted on another forum and the posted claims that the GM book referenced those part numbers to the LS6 head. If this is true, the LS2 heads are LS6 heads.
Todd
Todd
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Re: Gen III heads on LS2 (WhiteDiamond)
They LS2 head part numbers where posted on another forum and the posted claims that the GM book referenced those part numbers to the LS6 head. If this is true, the LS2 heads are LS6 heads.
Todd
Todd
Going ahead and doing the math, increasing the bore from GEN III to LS2 3.9 to 4 inches using the LS6 combustion chamber size, which I show listed at 64.5. This indeed calcs out to the advertised LS6 to LS2 CR of 10.5 to 10.9.
So the chamber size is the same, so mabey its just some runner revision.
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St. Jude Donor '15
Re: Gen III heads on LS2 (kewlbrz)
You have a interesting point. I was surprised when that info was posted, the cross reference to LS6 heads, as GM release info on the LS2 states the LS2 head is based on the LS6 head with slight revisions to runner design.
Todd
Todd
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Re: Gen III heads on LS2 (kewlbrz)
with a 4.00 bore vs 3.900 bore the big boost in power comes from unshroulding the valves. that could account for the rise in max RPM of the LS-2 engine. NASCAR 358 cu in engines use a 4.155 max bore allowed by NASCAR with a short stroke of 3.30 to unshrould the valves
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Re: Gen III heads on LS2 (clem zahrobsky)
I agree and wonder why GM would leave the CC alone with a larger bore. There are well documented flow increases for LS1/LS6 heads reworked for the larger bore motors. The additional bore size helps, but it does allow some simple changes in the CC's that I figured they would take advantage of(assuming the LS2s are really LS6s, hopefully this turns out to be false as they come to market).
Todd
Todd
