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Which heads would you choose?

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Old Dec 27, 2006 | 04:09 PM
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Default Which heads would you choose?

I'm contemplating a heads/cam swap for the GTO (LS1). The cam specs are 215/232 .598/.579 on a 118LSA. I'm trying to decide between two cylinder head options. Both sets of heads have been fully reconditioned, valve jobs, guides and pressure checked, etc. and will come with flow sheets...

Option #1: (used) Factory 241's ported and polished by hand at a reputable race shop, milled to 62cc chambers, intake port measures 215cc, exhaust 78cc, and flow numbers are 285cfm @ .600 on intake, 215cfm on exhaust side. Cost w/ valvetrain set up the way I spec = $930

Option #2: (new) Factory 243's CNC'd by a popular vendor, milled to 62cc chambers, intake port measures 227cc, exhaust 80cc, and flow numbers are 300cfm @ .600 on intake, 215cfm on exhaust side. Cost = $1350 (again, to my valvetrain specs)

Granted, the 243's flow a tad better, but with a larger port(s). I know the 243's are supposed to have a better / more efficient combustion chamber... is it enough to justify the extra cost?

The 241's would maintain "factory" look, for whatever that counts... and I am kinda going with the whole "sleeper" approach with this car...

Car will be running aftermarket intake, LS6 intake manifold (stock), LT headers w/cats, factory exhaust; through a T-56 tranny.

If anybody can think of something I've missed here, please feel free to point it out. Looking for thoughts and opinions....
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Old Dec 27, 2006 | 04:18 PM
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i'de choose AFR 205cc's.
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Old Dec 27, 2006 | 04:59 PM
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CNC LS6s w/o a doubt
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Old Dec 27, 2006 | 05:13 PM
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Go with the 243's.
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Old Dec 27, 2006 | 05:22 PM
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243s thats my pick
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Old Dec 27, 2006 | 06:50 PM
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TSP/PRC 5.3 ltr stage 2.5 would be a great choice
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Old Dec 27, 2006 | 06:53 PM
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i've got 243s, you know what i'd say!
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Old Dec 27, 2006 | 06:55 PM
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I think Patriot has a deal on their 243s right now too.
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Old Dec 27, 2006 | 09:31 PM
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well i did thaught about that before when i was about to stall my heads but in the end i choose dart 205 affordable ,milled and large valves. its simply fantastic
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Old Dec 27, 2006 | 11:12 PM
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Originally Posted by 99blancoSS
TSP/PRC 5.3 ltr stage 2.5 would be a great choice
+1...
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Old Dec 28, 2006 | 08:15 AM
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sleeper? then 241 if your current heads say 241 ..... and try negotiating the price .... if it has bigger valves and you`ll have to flycut the pistons and the polishing will show that the heads are not stock (dull not polished) then screw it prc 2.5 5.3 flycutting or prc 1 ls6 if you don`t need and won`t flycut (not sure when milled to the 62 chamber that you want) or patriot stock valved 243 or that livernois.

just an opinion.

Last edited by Bader-X; Dec 28, 2006 at 08:21 AM.
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