INTERNAL ENGINE MODIFICATIONS Valvetrain |Heads | Strokers | Design | Assembly

gains from 243/799 heads?

Old Feb 13, 2011 | 03:19 PM
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Default gains from 243/799 heads?

what gains would i see from a set of 243 or 799 heads? i have stock 862 ones right now, i know these are still "stock heads" but from everything ive read the 799 SHOULD bolt straight up no mods such as having them shaved down, unlike the 243's. is that correct? found a set on ebay for cheap so was wondering before i consider bidding/buying
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Old Feb 13, 2011 | 03:24 PM
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From: Bako
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243s and 799s are the same head. As far as gains, I am not sure. I believe you need to shave them some tho or you will lose CR..
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Old Feb 13, 2011 | 06:10 PM
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well dang i was hoping to get away with no shaving the 799's cause they are off a 5.3, i know they flow better than what i have, was gona do this cause spending 1500+ on heads just isnt in the budget right now
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Old Feb 13, 2011 | 06:48 PM
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From: Bako
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I believe the new 5.3s had Flat top pistons tho to help with increasing CR. Its only like $75-100 to have them Milled, And you can find the 799/243s for $3-500 all day long on tech and some are already milled..
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Old Feb 15, 2011 | 12:25 PM
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From: van nuys CA
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Originally Posted by D_reks{5.3}
I believe the new 5.3s had Flat top pistons tho to help with increasing CR. Its only like $75-100 to have them Milled, And you can find the 799/243s for $3-500 all day long on tech and some are already milled..
Correct flat top piston with 799 heads is 9.9:1.. he needs to shave them like. 025 to get compression back to stock.. great heads I believe should open up the top end. But im no expert..
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Old Feb 15, 2011 | 12:36 PM
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well for the money i believe im gona get them, just gota do some reading to findout EXACTLY how much to have them shaved and find a place thatll do it. theres a place local thats SUPPOSED to do heads, but when i called and told him i wanted my 862's ported they said they wouldnt touch em.
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Old Feb 15, 2011 | 12:40 PM
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I need to get them from 64.5 to 61cc.. at. 007 per cc ur looking like at. 024 for ur stock compression but I just say go. 030 that's what I cut mine. Its more compression witch means more torque. But that's just me.
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Old Feb 15, 2011 | 02:01 PM
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Go ahead and shave them bitches 0.040!!! will have killer torque!
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Old Feb 15, 2011 | 02:32 PM
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Originally Posted by 00buckshot
Go ahead and shave them bitches 0.040!!! will have killer torque!
Why stop there... shave them .050 and run a .027 head gasket. Talk about PTV issues. :nunchuk1:
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Old Feb 15, 2011 | 02:34 PM
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Originally Posted by 05gmcsierra
I need to get them from 64.5 to 61cc.. at. 007 per cc ur looking like at. 024 for ur stock compression but I just say go. 030 that's what I cut mine. Its more compression witch means more torque. But that's just me.
What did you end up using for a head gasket? Stock thickness.

I've got a set of 243's shaved .03 and gonna match it with a .03 head gasket for a total of .049. Was wondering if anyone else has tried this, I was in another thread that someone shaved theirs down .05 with no ptv issues, so I feel safe with that.
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