PRC CNC ported LS3 heads & 226/238 .600/.612 dyno!
06-02-2015, 08:23 AM
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PRC CNC ported LS3 heads & 226/238 .600/.612 dyno! Dyno jet numbers 467/433
Safe tune for road racing: AF is 12.4-12.6 in the TQ band and 12.2 at redline, timing 23* max.
Wonder if I mill the heads .020 will I pick up some TQ?
LS3 short block with -4cc Mahle pistons
Safe tune for road racing: AF is 12.4-12.6 in the TQ band and 12.2 at redline, timing 23* max.
Wonder if I mill the heads .020 will I pick up some TQ?
LS3 short block with -4cc Mahle pistons
Last edited by Z06VENOM; 06-02-2015 at 09:14 AM.
06-02-2015, 12:38 PM
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Oh a c5 nice a 500 lbs. advantage over must others, you got ls7 power now!
What heads those you have on there? don't look Chevy to me.
Have a grand sport I'm working on a heads and cam rite now as well.
What did you do for axel back exhaust, cheers.
What heads those you have on there? don't look Chevy to me.
Have a grand sport I'm working on a heads and cam rite now as well.
What did you do for axel back exhaust, cheers.
06-02-2015, 01:36 PM
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Staging Lane
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I am actually a bit on the low side for power... Guys with similar cam and heads are making around 500wheel.
I am running the TSP headers, borla off-road X pipe and TI mufflers with bypass tube. The car was wayyyy to load with straight pipes. They gave me a hard time at the track.
Heads are from Texas Speed, LS3 CNC ported castings with 68 or 70cc chambers. Someone commented on another thread that my compression is 10.2:1
Just waiting for Jason from to get back to me so I can pull the heads and mill them down to up the compression a bit.
Custom cam using LXL lobes, stock LS3 intake, stock (for now) LS2 throttle body and Airaid LS7 cold air.
Thanks
06-02-2015, 04:44 PM
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Huge chamber and flycuts will loose some more.
You could cut 100thou and still have heaps of ptv. Heck even go to 230ish/240ish and still have clearance (always check ptv though)
You could cut 100thou and still have heaps of ptv. Heck even go to 230ish/240ish and still have clearance (always check ptv though)
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06-02-2015, 05:33 PM
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Else important is what compression does he really have now so cc the chambers first, machine shop don't charge for it if he does the job there.
Ls3 have 10.7 compression from the get-go.
06-03-2015, 03:25 AM
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06-03-2015, 05:45 AM
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And yeah I will check ptv thanks
06-03-2015, 05:59 AM
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Another question for you guys... Will it be worth all the trouble?
How much will I gain going to 10.7? And I read somewhere that 11:1 - 11.1:1 is the sweet spot for these motors, is that true? If I am going to go cut might aswell go all the way...
How much will I gain going to 10.7? And I read somewhere that 11:1 - 11.1:1 is the sweet spot for these motors, is that true? If I am going to go cut might aswell go all the way...
06-03-2015, 07:36 AM
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What my good buddy Camster said is the best route to go if milling. I could not have put it better myself. @ most milling the heads would get you + 20 rwtq or rwhp. Now you have 2 weigh your options on breakin the engine down and chasing every little Hp gremlin. You can get up 2 : around 11:5 depending on if the cam can bleed off cylinder pressure. They like around 190 to 200 psi in the cylinders on pump.
06-03-2015, 05:02 PM
#17
Here is my .02. the compression should get back to 10.7 min. The cam is definately small but not alot. lift is ggod for endurance but the timing @23 deg is pretty low especially with the less than 10.7:1. 26-28 usually makes best power but is getting close to the edge for pump.
06-08-2015, 10:06 PM
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Be nice with about 11.3 compression so he can crank the total wide open throttle ignition timing with the gas available to him but again OP must first find out the combustion chamber cc so we know how much to mill off.
10-11-2015, 04:46 PM
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Sorry for the late update...
I ended up milling the heads to get to 11.3CR, ported the intake and throttle body. I retuned on the track but never made it back to the dyno.
The car does feel stronger and lasted a full season. 5 time attack, 5 practice days and 2 test and tune, so 12 days total and 1 day just for fun to make this video.
3 wins and 2 second place finishes.
Turn up the sound!! enjoy.
I ended up milling the heads to get to 11.3CR, ported the intake and throttle body. I retuned on the track but never made it back to the dyno.
The car does feel stronger and lasted a full season. 5 time attack, 5 practice days and 2 test and tune, so 12 days total and 1 day just for fun to make this video.
3 wins and 2 second place finishes.
Turn up the sound!! enjoy.
