Porting my LS3 heads
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Teching In
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Porting my LS3 heads I have a 2008 A6 vert and want to get some more HP and wanted some opinions and or real world experience on the gains with porting the LS3 heads. Here are the current mods:
1 7/8 Kooks headers
Haltech CAI
227/231 .614/.617 115+3 LSA Cam
3.42 gears
Tune
Here are the flow numbers if I get them ported:
Flow Numbers
Intake Exhaust
.100 80.9 60.3
.200 159.9 129.9
.300 237.1 180.1
.400 291.2 226.0
.500 330.8 255.9
.600 365.9 268.1
.700 376.6 272.1
Thanks
Ken
1 7/8 Kooks headers
Haltech CAI
227/231 .614/.617 115+3 LSA Cam
3.42 gears
Tune
Here are the flow numbers if I get them ported:
Flow Numbers
Intake Exhaust
.100 80.9 60.3
.200 159.9 129.9
.300 237.1 180.1
.400 291.2 226.0
.500 330.8 255.9
.600 365.9 268.1
.700 376.6 272.1
Thanks
Ken
Last edited by ktoonsez; Jan 27, 2011 at 09:54 AM.
I have a 2008 A6 vert and want to get some more HP and wanted some opinions and or real world experience on the gains with porting the LS3 heads. Here are the current mods:
1 7/8 Kooks headers
Haltech CAI
227/231 .614/.617 115 LSA Cam
3.42 gears
Tune
Here are the flow numbers if I get them ported:
Flow Numbers
Intake Exhaust
.100 80.9 60.3
.200 159.9 129.9
.300 237.1 180.1
.400 291.2 226.0
.500 330.8 255.9
.600 365.9 268.1
.700 376.6 272.1
Thanks
Ken
1 7/8 Kooks headers
Haltech CAI
227/231 .614/.617 115 LSA Cam
3.42 gears
Tune
Here are the flow numbers if I get them ported:
Flow Numbers
Intake Exhaust
.100 80.9 60.3
.200 159.9 129.9
.300 237.1 180.1
.400 291.2 226.0
.500 330.8 255.9
.600 365.9 268.1
.700 376.6 272.1
Thanks
Ken
There was a recent article in Hot Rod Magazine that compared 11 cylinder heads and the bigger CFM heads did not make the power you would have thought. You may want to look up that article on the Hot Rod magazine website.
I personally would be concerned about keeping port velocity high. Ports that are too large could hurt the torque curve. Especially since you have the A6. Big CFM tells me the ports are larger and that means lower velocity to me.
There was a recent article in Hot Rod Magazine that compared 11 cylinder heads and the bigger CFM heads did not make the power you would have thought. You may want to look up that article on the Hot Rod magazine website.
There was a recent article in Hot Rod Magazine that compared 11 cylinder heads and the bigger CFM heads did not make the power you would have thought. You may want to look up that article on the Hot Rod magazine website.
You will not gain much from the ported heads alone. The stock heads you have already flow more than the engine can use. I would get a fast intake and port match it to the heads, underdrive pulley, and get the exhaust opened up behind the headers. Did you go with stronger valve springs? A better converter in your trans will make the car accelerate like it has a lot more hp also.
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On The Tree
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From: akron ohio
Not worth it to port them. When you see hp gains on ported ls3 head most of that gain came from the mill. If you just mill the head and leave it stock otherwise you will see the same gain. However you will kill you ptv clearance. If you mill them I would keep the cam around 224 ish intake duration.
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Teching In
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You will not gain much from the ported heads alone. The stock heads you have already flow more than the engine can use. I would get a fast intake and port match it to the heads, underdrive pulley, and get the exhaust opened up behind the headers. Did you go with stronger valve springs? A better converter in your trans will make the car accelerate like it has a lot more hp also.
Yes I do have Patroit gold extreme's. I have wanted to go to a new converter but it doesn't seem like there are any good ones out there that you can trust not to blow up the tranny. Have seen 6 people and heard of countless others that lost there tranny due to aftermarkets stalls.
on my old Z-28 i had a 3000 stall with a B&M cooler and billet servos.i pounded the hell out of that car with no problems.
i did have the tranny flushed when i added the converter.
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Teching In
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i have seen a few failures,but that was due to either not running a tranny cooler or the wrong stall for the application.of course this was on the F-Bods with the 4L60E.
on my old Z-28 i had a 3000 stall with a B&M cooler and billet servos.i pounded the hell out of that car with no problems.
i did have the tranny flushed when i added the converter.
on my old Z-28 i had a 3000 stall with a B&M cooler and billet servos.i pounded the hell out of that car with no problems.
i did have the tranny flushed when i added the converter.
When I think about this, will it actually help? My car spends all its time from 3000-6500 RPM. Would it help due to being looser than the stock one? I was always under the assumption that it just help from the RPM of your old stall to the point of the new one, I.E. at 3200 stall would help accelerate better from the stock point of 1400 RPM to the new 3200?
Launching!
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It makes 350rwtq at 2750 and made 411rwtq by 4500 (table flat torque) peaked with 467rwhp at 6500RPM.
with a stock clutch M6 tranny
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Another option I am starting to consider:
Thinking about doing a head swap for Mast Black Label Med. Bore. Anybody done this swap on LS3 or similar bore/ci engine? They are saying 50-75 HP with the swap with my current setup.
Thinking about doing a head swap for Mast Black Label Med. Bore. Anybody done this swap on LS3 or similar bore/ci engine? They are saying 50-75 HP with the swap with my current setup.
I'd look into Texas Speed. Jason and those guys have spent a lot of time testing various cam and head combos. I think they've got a good $-friendly CNC ported LS3 head, I'd go contact them and see. I think when you compare stock ported vs aftermarket, I'd look at the cost and results and see if the cost is worth it. Only reason I suggest you stick to stock ported heads is that your cam is not very big so I'd keep it simple.
Thread Starter
Teching In
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I'd look into Texas Speed. Jason and those guys have spent a lot of time testing various cam and head combos. I think they've got a good $-friendly CNC ported LS3 head, I'd go contact them and see. I think when you compare stock ported vs aftermarket, I'd look at the cost and results and see if the cost is worth it. Only reason I suggest you stick to stock ported heads is that your cam is not very big so I'd keep it simple.
LS3's work well with mild cams so I'd be surprised to see you gain 50 HP with a head swap. If you make the move, and assuming your cam is well tuned now, I'd expect closer to 30 RWHP assuming you get a mild CR bump in the swap too. I'm hoping I'm wrong, b/c if 60 RWHP could be obtained from swapping heads, 530 RWHP here I come.
