5.3 vs 5.7 LS1 Heads > Why over 11.0 -1 CR needed on pump gas?
#22
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Ron,
The CNC program for the 5.7 and 5.3 intake and exhaust ports is IDENTICAL, but there is nothing you can do with the 5.7 chamber at 67cc. However the 5.3 chamber is around 58cc stock, so we reshape it with our CNC program, it ends up at 63cc and has a slightly better shape on intake and exhaust, especially on the exhaust side, where the CNC 5.3 chamber picks up the exh port flow almost 15 cfm and the intake advantage is just a few cfm. We have a new head package available too, it is called the Stage 1.5, please don't laugh. The 2.02 Ferrea intake valve is worth almost 30 cfm over the stock 2.00 5.7 valve, but we have a truck exhaust 1.55 valve that is tulip in shape and flows MORE then the Ferrea 1.55 exhaust valve, to the tune of almost 15 cfm in the mid lift. It will be $1664 retail price with the same Comp dual springs, tit. ret. etc. The increased exhaust flow probably will not help N/A performance but it will help the pocket book $136, good luck on whatever you decide. BTW, how does kimchee taste, I don't see that on the menu at my Chinese resturant. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Brian Tooley @ TotalEngineAirflow.com
The CNC program for the 5.7 and 5.3 intake and exhaust ports is IDENTICAL, but there is nothing you can do with the 5.7 chamber at 67cc. However the 5.3 chamber is around 58cc stock, so we reshape it with our CNC program, it ends up at 63cc and has a slightly better shape on intake and exhaust, especially on the exhaust side, where the CNC 5.3 chamber picks up the exh port flow almost 15 cfm and the intake advantage is just a few cfm. We have a new head package available too, it is called the Stage 1.5, please don't laugh. The 2.02 Ferrea intake valve is worth almost 30 cfm over the stock 2.00 5.7 valve, but we have a truck exhaust 1.55 valve that is tulip in shape and flows MORE then the Ferrea 1.55 exhaust valve, to the tune of almost 15 cfm in the mid lift. It will be $1664 retail price with the same Comp dual springs, tit. ret. etc. The increased exhaust flow probably will not help N/A performance but it will help the pocket book $136, good luck on whatever you decide. BTW, how does kimchee taste, I don't see that on the menu at my Chinese resturant. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Brian Tooley @ TotalEngineAirflow.com
#23
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What about the LS6 heads, I would imagine they flow better then Ls1 heads stock but do they hold any advantage when ported? What size chambers do they have, is it the same as the 5.3? I would love to gain some more horse on my head cam car by switchig to LS6 or 5.3s for the extra compression. But if the 5.3 can pull the same CFM as the LS6 and produce the same compression I would rather go with the less expensive 5.3
#24
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I'm imbarrased to admit this, but our R&D on the LS6 head has not been very promising, it flows less then the our 5.3 with the same components (2.02/1.55 valves) unless we really hog the snot our of it, but then its 235+ cc
#25
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[QUOTE] "BTW, how does kimchee taste, I don't see that on the menu at my Chinese resturant".
Kimchee really is pretty good. Not always good to smell (lots of garlic), but not bad. Strictly a Korea food.
As for the name "Kimchee and Rice"... Well, it's really a stupid name to say the least. Just have been using it since I have been here in Korea. When I return to the states, I will change my username to something not so silly. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Still need to talk to you again about some heads. Hey, I saved those price quotes I got from you about 5 months ago when I was visiting my mother in Phoenix (Sun City). I just don't know when I will be leaving here. Should be very soon though. Not long at all.....
Ron Larson,
Kimchee really is pretty good. Not always good to smell (lots of garlic), but not bad. Strictly a Korea food.
As for the name "Kimchee and Rice"... Well, it's really a stupid name to say the least. Just have been using it since I have been here in Korea. When I return to the states, I will change my username to something not so silly. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Still need to talk to you again about some heads. Hey, I saved those price quotes I got from you about 5 months ago when I was visiting my mother in Phoenix (Sun City). I just don't know when I will be leaving here. Should be very soon though. Not long at all.....
Ron Larson,
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Higher flow, less money?
Sounds like a plan!
So, If I would go from stock to stage 1.5, 5.3L heads w/ a thunder 224/114, the 11:1 compression wouldn't hurt? BTW, in PA we can get 93 octane everywhere, 94 at Sunoco.
Sounds like a plan!
So, If I would go from stock to stage 1.5, 5.3L heads w/ a thunder 224/114, the 11:1 compression wouldn't hurt? BTW, in PA we can get 93 octane everywhere, 94 at Sunoco.
#28
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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 WMSuperSport:
<strong>A Warning About Milling: Too much will cause intake manifold to head complications in geometry.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">true but you can go up to .050thous and not have a problem.
<strong>A Warning About Milling: Too much will cause intake manifold to head complications in geometry.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">true but you can go up to .050thous and not have a problem.
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I had the 5.3 heads that were milled .030 over, and I smoked a piston on my way home from arizona. I never could get rid of the detonation unless I mixed in a couple gallons of 100 unleaded from 76. I would go the 10.8 route if the engine is for a daily driver. A little extra compression is not worth the expense of having to build a new engine. My family lives in Arizona and that summer heat is hard on the cars.