Waffling on heads.. want ls6 cnc'd
#1
Waffling on heads.. want ls6 cnc'd
Have some 241 casting that I was going to home port. Wasnt going to do anything fancy just smooth off the bumps and mimick a few pictures. How much of a better increase in flow will I get. I already should pick up a little for using the better casting. For $1340 I can get bare ls6 casting delieverd and gain about 84 overall more flow. But with the ls6 cnc'd for $2043 delivered I gain 202 more total... big diff but its also $673 more. Wife would kill me if she knew how much I already spent but DAMN those heads flow nice in the middle right where my cam would love it. Then I could already have them in place for when the bottom end needs to be redone.
But if I can pick up decent numbers with a home port then I'll save the money.
But if I can pick up decent numbers with a home port then I'll save the money.
#3
Originally Posted by Cal
I recently dynoed 431 rwhp on home ported heads with no milling and stock valves. 241 castings. Only cost me about $30 in burrs and sanding rolls, but my wife still bitched because the garage was a mess of aluminum chips.
#5
LS1 Tech Administrator
iTrader: (14)
The port isn't as much of a restriction as the valve area. Unless you have special equipment that can do trick valve jobs and bowl blending, you might be disappointed with your results. About 80% of the flow gains come from the valve area.
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
#6
TECH Veteran
iTrader: (1)
True, since I did the porting and installed the cam at the same time, hard to say how much the porting helped. I've only seen one other dyno chart for a car with this cam; it made 420 rwhp, but no information on other mods. The only thing I know for sure is that the porting didn't hurt the engine any. But compared to $1500 for a set of professionally ported heads, I'm not complaining.
Bigger valves and milling for higher compression would have been nice, but I just didn't have the time and money. Maybe next time I have the heads off I will do that. As far as the porting itself, there are some obvious things you can take care of without getting really fancey. You can take out the rocker bolt bulge, remove the swirl ramp, blend the valve seats into the bowl area, tapper back the valve guide boss, and just do a general smoothing and blending of the casting imperfections. You don't want to really hog out the ports and remove a lot of metal or you're going to lose flow velocity. Just a general cleanup.
As far as trick valve jobs, the stock one is a pretty nice three angle job, much better than what LT1's have from the factory. I don't know how you could improve on that much without going to bigger valves.
Bigger valves and milling for higher compression would have been nice, but I just didn't have the time and money. Maybe next time I have the heads off I will do that. As far as the porting itself, there are some obvious things you can take care of without getting really fancey. You can take out the rocker bolt bulge, remove the swirl ramp, blend the valve seats into the bowl area, tapper back the valve guide boss, and just do a general smoothing and blending of the casting imperfections. You don't want to really hog out the ports and remove a lot of metal or you're going to lose flow velocity. Just a general cleanup.
As far as trick valve jobs, the stock one is a pretty nice three angle job, much better than what LT1's have from the factory. I don't know how you could improve on that much without going to bigger valves.
#7
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1300 for bare ls6 heads?? you'll spend more than that on valves/sprigns etc than getting a set from say TEA or some other porter...
you can find used ls6 heads for less than 800 if you shop around..
you can find used ls6 heads for less than 800 if you shop around..