5.3 vs 243 Heads...Confusion
06-03-2007, 12:53 AM
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Originally Posted by Okie5.3
i believe over on tech someone was saying .006"=1cc for the 243's. which should mean in the neighborhood of .032-.036".
http://www.sdparts.com/product/88958...ccChamber.aspx
"Best buy on the planet! Unbelievable performance from fully CNC ported cylinder heads. Some of the best low and mid-lift numbers we have ever seen from a stock size valve. These heads will flow over 200cfm at 0.300" lift and 290+ at 0.500". Fully assembled with the 2002 Z06 light-weight valves and the new "02 valve springs. These heads have been milled 0.055" to bring the combustion chambers back down to approximately 60.9cc. Care must taken to check pushrod length and proper intake installation when using these cylinder heads. Price is for each cylinder head"
06-03-2007, 08:15 AM
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Originally Posted by silent1
It wasn't a guess, .055" for a 60.9cc chamber:
http://www.sdparts.com/product/88958...ccChamber.aspx
"Best buy on the planet! Unbelievable performance from fully CNC ported cylinder heads. Some of the best low and mid-lift numbers we have ever seen from a stock size valve. These heads will flow over 200cfm at 0.300" lift and 290+ at 0.500". Fully assembled with the 2002 Z06 light-weight valves and the new "02 valve springs. These heads have been milled 0.055" to bring the combustion chambers back down to approximately 60.9cc. Care must taken to check pushrod length and proper intake installation when using these cylinder heads. Price is for each cylinder head"
http://www.sdparts.com/product/88958...ccChamber.aspx
"Best buy on the planet! Unbelievable performance from fully CNC ported cylinder heads. Some of the best low and mid-lift numbers we have ever seen from a stock size valve. These heads will flow over 200cfm at 0.300" lift and 290+ at 0.500". Fully assembled with the 2002 Z06 light-weight valves and the new "02 valve springs. These heads have been milled 0.055" to bring the combustion chambers back down to approximately 60.9cc. Care must taken to check pushrod length and proper intake installation when using these cylinder heads. Price is for each cylinder head"
06-03-2007, 08:17 AM
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Originally Posted by Okie5.3
i believe over on tech someone was saying .006"=1cc for the 243's. which should mean in the neighborhood of .032-.036".
Where you been Okie? Get any of those new parts on yet?
06-03-2007, 11:35 AM
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Originally Posted by tdrumm
But what you are missing is that when the chamber of a head is ported (as in this "fully CNC ported" example), it gets larger. So it takes some milling to get them back to 65cc after the porting, and then even more to bring the chamber size down.
06-03-2007, 08:33 PM
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Originally Posted by tdrumm
But what you are missing is that when the chamber of a head is ported (as in this "fully CNC ported" example), it gets larger. So it takes some milling to get them back to 65cc after the porting, and then even more to bring the chamber size down.
Originally Posted by tdrumm
Where you been Okie? Get any of those new parts on yet?
if your tired of those junky old WCCH heads i'll trade ya out for some stock 243's and 5.3s. you might have to kick in a little $$$ for the trade though...
06-04-2007, 06:55 AM
#47
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Originally Posted by trever1t
Hmm, are the 799 castings chambered / valved differently for the 5.3's than the LS6's? Are they that hard to find?
06-04-2007, 07:02 AM
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Originally Posted by Okie5.3
if your tired of those junky old WCCH heads i'll trade ya out for some stock 243's and 5.3s. you might have to kick in a little $$$ for the trade though...
After what I went through the first time swapping heads, I'm not ever going to take them off again. 
sent ya a pm as to not ***** up this thread.
06-11-2007, 09:55 PM
#50
Would it not be easier since the price of heads have come down so far for these motors to just buy a set of Patriots or AFRs? I am not trying to be a smart *** just wondering if these stock heads worked are that good or if this is a good way to save a couple hundred bucks or so. I have a friend that will give me a set of LS1 heads....if these are that good I might consider it.