862/706 vs 243
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862/706 vs 243 I know stock vs stock the 243 is the superior head but my engine came with 706 non crack-tec heads and I'd like to use them if I could. My question is what performs better, a stock 243 or a professionally hand ported 862/706 because for the price of 243s I could have my 706s hand ported and flowed by a well known drag racer/engine builder in my area. I also know that I'm going to want to mill the 243s if I get them because my set up is a 5.3 with 4.8 flat tops and I want to stay around 10.5-1. Are 243s just such a superior head vs the 706 or could the 706 out perform the 243 with alittle work?
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From: Central Cal.
Look for 799's as they are identical, and came on every 5.3 truck engine since about '07. Prices should not be too bad, as common as they are. I'm surprised 243's haven't come down more in light of this.
799 and 243 heads were used on all 2007.5-2013 4.8 and 5.3, as well as previous years but on certain ones.
Some Pick-A-Part/Pick-N-Pull Yards have great prices on parts. My local yard sells aluminum non-overhead cam heads for $44.00 ea. with a $10 Core. I can get a set of 243/799 heads any day of the week down there for $120 out the door without cores and $100 with cores. So if you would rather spend your money on 243 heads, check your local junkyard first.
In Stock Form, the Cathedral Port 243/799 are the best flowing GM Production heads for Sub 4.00" Bores in a N/A Setup, at least in my opinion. Above 4.00" Bores, 6.0L+, it can vary depending on your setup.
Some Pick-A-Part/Pick-N-Pull Yards have great prices on parts. My local yard sells aluminum non-overhead cam heads for $44.00 ea. with a $10 Core. I can get a set of 243/799 heads any day of the week down there for $120 out the door without cores and $100 with cores. So if you would rather spend your money on 243 heads, check your local junkyard first.
In Stock Form, the Cathedral Port 243/799 are the best flowing GM Production heads for Sub 4.00" Bores in a N/A Setup, at least in my opinion. Above 4.00" Bores, 6.0L+, it can vary depending on your setup.
I just saw a dyno video in which in stock form the 706 head beat stock 799 heads by 2 hp. But if you plan on getting them ported, I think the 799/243 head is a better choice since they have larger valves stock and can fit 2.02 valves.
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I know stock vs stock the 243 is the superior head but my engine came with 706 non crack-tec heads and I'd like to use them if I could. My question is what performs better, a stock 243 or a professionally hand ported 862/706 because for the price of 243s I could have my 706s hand ported and flowed by a well known drag racer/engine builder in my area. I also know that I'm going to want to mill the 243s if I get them because my set up is a 5.3 with 4.8 flat tops and I want to stay around 10.5-1. Are 243s just such a superior head vs the 706 or could the 706 out perform the 243 with alittle work?
799 and 243 heads were used on all 2007.5-2013 4.8 and 5.3, as well as previous years but on certain ones.
Some Pick-A-Part/Pick-N-Pull Yards have great prices on parts. My local yard sells aluminum non-overhead cam heads for $44.00 ea. with a $10 Core. I can get a set of 243/799 heads any day of the week down there for $120 out the door without cores and $100 with cores. So if you would rather spend your money on 243 heads, check your local junkyard first.
In Stock Form, the Cathedral Port 243/799 are the best flowing GM Production heads for Sub 4.00" Bores in a N/A Setup, at least in my opinion. Above 4.00" Bores, 6.0L+, it can vary depending on your setup.
Some Pick-A-Part/Pick-N-Pull Yards have great prices on parts. My local yard sells aluminum non-overhead cam heads for $44.00 ea. with a $10 Core. I can get a set of 243/799 heads any day of the week down there for $120 out the door without cores and $100 with cores. So if you would rather spend your money on 243 heads, check your local junkyard first.
In Stock Form, the Cathedral Port 243/799 are the best flowing GM Production heads for Sub 4.00" Bores in a N/A Setup, at least in my opinion. Above 4.00" Bores, 6.0L+, it can vary depending on your setup.
On The Tree
Joined: Oct 2011
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From: Dirty South
After seeing Richards head shootout, I called my machinest. $400 gets my 862’s intake valve seats machined to accept the stock ls1 valves, and a 7 angle valve job. 11:1 unmilled on my ls1. That’s what’s I’m doing.
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From: Euless, TX