How do the GM CNC LS6 heads compare to the average Stage 2 LS1 head?
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I think you should specify exactly what stage 2s you are looking to compare them to, as you well see a lot of variance.
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I've seen the GMPP CNC LS6 heads flowed on the same bench as a set of "stage II" 6.0L heads. The LS6 heads had the stock 2"/1.55" valves, and the 6.0L heads had 2.055"/1.6" valves. Both heads flowed nearly identical up to .500" lift. Past that, the LS6 heads flowed an additional 8-10 cfm more. On this bench, the CNC LS6 heads flowed right at 308 cfm at peak. This just goes to show you how larger valves aren't needed to get the flow #'s when ported properly. FYI, the "stage II" 6.0L heads were bolted onto a stock-cid LS1 with a 228/228 XE-R cam, and it put down 440 RWHP in an M6 C5.
Trevor
<small>[ October 15, 2002, 10:34 PM: Message edited by: Trevor D ]</small>
Trevor
<small>[ October 15, 2002, 10:34 PM: Message edited by: Trevor D ]</small>
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Larger valves are needed if you want good flow with some volocity left. Bolt both those heads on the same car and see the diff. Those cnc heads are going to have nothing under the curve. They will both requier totally differant cams.
Nate
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That's horseshit. Valve size has very little to do with flow. I've seen ported 6.0L heads with stock 2.00/1.55 valves outflow the best 5.7/5.3 LS1 heads with 2.055/1.60 valve by 20 numbers at .200, .300, .400, and .500 lift. The port is more of the limitation than the valve. Bigger valves are more of a marketing game than anything.
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
![](https://ls1tech.com/forums/signaturepics/sigpic210_1.gif)
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
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Wasn`t one of the sponsers selling them for dirt cheap? Like $749 ea w/o valves/springs?? SDPC? I have the money for a set at that price, but then I`d have to come up with even more cash for the divorce attorney! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
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[QUOTE]Originally posted by 02 Silver Z:
<strong>Wasn`t one of the sponsers selling them for dirt cheap? Like $749 ea w/o valves/springs?? SDPC? I have the money for a set at that price, but then I`d have to come up with even more cash for the divorce attorney! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> </strong>[/QUOTE
Hehehe! <img border="0" alt="[jester]" title="" src="graemlins/gr_jest.gif" /> BUT she can't bring you happiness like those heads would.
<img border="0" alt="[Camaro]" title="" src="graemlins/camaro.gif" />
<strong>Wasn`t one of the sponsers selling them for dirt cheap? Like $749 ea w/o valves/springs?? SDPC? I have the money for a set at that price, but then I`d have to come up with even more cash for the divorce attorney! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> </strong>[/QUOTE
Hehehe! <img border="0" alt="[jester]" title="" src="graemlins/gr_jest.gif" /> BUT she can't bring you happiness like those heads would.
<img border="0" alt="[Camaro]" title="" src="graemlins/camaro.gif" />
#10
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I thought they already cam assembled from GM. I'm just thinking that this would be an inexpensive way to get some LS6 heads, and one could play with the porting more on down the road.
On a big cube motor (422-427), I think it would put down respectable #, in comparison to a set of LS1 stage 2, from ARE, MTI, GTP, etc.
No core charge, and if you got a friend at the dealer, you could probably get them close to cost. Anyone know what the GM dealer cost is on these heads?
I dont have the part #, could someone post it so I can call & find out some prices? Thanks
On a big cube motor (422-427), I think it would put down respectable #, in comparison to a set of LS1 stage 2, from ARE, MTI, GTP, etc.
No core charge, and if you got a friend at the dealer, you could probably get them close to cost. Anyone know what the GM dealer cost is on these heads?
I dont have the part #, could someone post it so I can call & find out some prices? Thanks
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i have these heads with asa cam and made 407 sae rwhp and 384 sae rwtq i used 7.350 pushrods and that gave me 1 3/4 turns of preload
george
george
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SDPC also sells a bare ported LS6 head that has not been milled at all. These would be a much better choice for FI people.
Scott
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#13
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yeah, but how much would the valvetrain cost?
last i heard the 02 LS6 came with very exzpensive valves.
Ryan. <-- disapointed at the news on the milling <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> i knew there had to be a reason they were not more popular.
last i heard the 02 LS6 came with very exzpensive valves.
Ryan. <-- disapointed at the news on the milling <img border="0" title="" alt="[Sad]" src="gr_sad.gif" /> i knew there had to be a reason they were not more popular.
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Well, you could buy stocked sized Ferra valves, springs and retainers for under $400.
Slap them together and you would have about $2000 into a set of LS6 heads.
Scott
Slap them together and you would have about $2000 into a set of LS6 heads.
Scott
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</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Scott 98Z M6:
<strong>Well, you could buy stocked sized Ferra valves, springs and retainers for under $400.
Slap them together and you would have about $2000 into a set of LS6 heads.
Scott</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">why would you want to use the ferra valves the zo6 are better they are way lighter and lighter valvetrain means more hp and they cost ya 2100 shipped with headgaskets and head bolts and 11to 1 is fine on pump gas just dont jack the timing they will make great power
george
<strong>Well, you could buy stocked sized Ferra valves, springs and retainers for under $400.
Slap them together and you would have about $2000 into a set of LS6 heads.
Scott</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">why would you want to use the ferra valves the zo6 are better they are way lighter and lighter valvetrain means more hp and they cost ya 2100 shipped with headgaskets and head bolts and 11to 1 is fine on pump gas just dont jack the timing they will make great power
george
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11:1 is not fine if you are going to be using the heads on an FI car...
That is primarily what I am looking at them for.
Scott
That is primarily what I am looking at them for.
Scott
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GMPP ( dunno about SDPC) CNC ported heads (ls6 or LS1) are done by Lingenfelter... hense the LPE that is stamped into them before the serial number.
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</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Scott 98Z M6:
<strong>11:1 is not fine if you are going to be using the heads on an FI car...
That is primarily what I am looking at them for.
Scott</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">why is it not fine i have a more then stock timing profile with a 12.8 a/f and not a bit of knock. with 11-1
<strong>11:1 is not fine if you are going to be using the heads on an FI car...
That is primarily what I am looking at them for.
Scott</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">why is it not fine i have a more then stock timing profile with a 12.8 a/f and not a bit of knock. with 11-1
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Are you running a force inducted setup on 11:1? At 12.8:1 AFR??? I seriously doubt it.
I meant Forced Induction when I said FI, not Fuel Injected...
Scott
I meant Forced Induction when I said FI, not Fuel Injected...
Scott