408 Ls3/l92 467/460
408 Ls3/l92 467/460 My tuner had the car on the dyno, it's not completely dialed in, but the basic numbers are in, she made 467rwhp at 5600rpm peak torque was just under 460 at 4250rpm on the mustang dyno. was told it started to get some valve float at 6300rpms dont have a graph for that one tho. clutch master took a dump, gonna rebuild it tomarrow and try to get it back to the tuner for the little adjustments
The engine is a 408 11.9:1compression iron block, ballanced, coated bearings, 249/255 .612" .620" on a 110LSA tsp cnc'd l92 heads shaved to 68cc chambers, stainless heavy valves, patriot golds, caddy lifters, molly pushrods, doubble roller timing chain, highvolume oil pump, high pressure spring, stock rocker arms, kooks 1 7/8" headers, 3" y pipe to a single 3" hooker catback.
to tell the truth i was expecting more, was looking for a "bigger cam" in the l92 setup but it looks like it may need some work. overall im happy with the first results.
EDIT 2009 Smaller PSI specified grind, made 496rwhp with bone stock l76 intake
The engine is a 408 11.9:1compression iron block, ballanced, coated bearings, 249/255 .612" .620" on a 110LSA tsp cnc'd l92 heads shaved to 68cc chambers, stainless heavy valves, patriot golds, caddy lifters, molly pushrods, doubble roller timing chain, highvolume oil pump, high pressure spring, stock rocker arms, kooks 1 7/8" headers, 3" y pipe to a single 3" hooker catback.
to tell the truth i was expecting more, was looking for a "bigger cam" in the l92 setup but it looks like it may need some work. overall im happy with the first results.
EDIT 2009 Smaller PSI specified grind, made 496rwhp with bone stock l76 intake
Last edited by CamaroRick; Apr 20, 2010 at 09:50 PM.
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Don't get hung up on the numbers...those are stout numbers on a mustang dyno. That is a good sized cam you are running there. About your peak at 5600 RPMs? So you are right...that makes me think there is more in there...you could have a couple of problems: slipping clutch, floating valvetrain or that cam should probably peak at 6500 or maybe a little higher. Did you degree the cam or install dot to dot and hope it was ground perfect? Sometimes I think degreeing is necessary (for max power), and sometimes the cam is ground perfect or nearly perfect so the valve events occur on time and give you max power. Just my $0.02
How did you get 11.9:1 CR? Is that with flat top pistons and what gasket?
PS...Can I or you add your set up to the 408 thread stickied at the top of this section?
How did you get 11.9:1 CR? Is that with flat top pistons and what gasket?
PS...Can I or you add your set up to the 408 thread stickied at the top of this section?
Last edited by ExceSSive; Jan 30, 2008 at 08:42 PM.
yea go right ahead, the cam was degreed and installed straight up, centerline's were right on
-1.8cc valve reliefs, 4.030 bore 4.000 stroke, .040" head gasket, 68cc chambers ~.01" above deck
-1.8cc valve reliefs, 4.030 bore 4.000 stroke, .040" head gasket, 68cc chambers ~.01" above deck
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You could also be starving for air up top too. Are you using the L76 intake? I don't know how they flow...Don't know alot about the L76/L92 set ups. Something is telling me if you had valve float on one run then the place to look for more power might be in the valve train...springs...etc (my opinion, maybe some experts can chime in). I see you have caddy lifters and they should be good to like 8000 RPMs. I don't know, you have good numbers but 5600 peak makes me think there may be more in it and there has to be a way to get it out. Get your clutch fixed and go at it again.
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From: Westampton, NJ
i doubt its valve float...looks to me like your inake has become a major restriction. Your lifters and valvetrain may be able to hold 8000rpm , but your intake certainly isnt (hell its barely capable of 6000RPM). try porting the intake and TB or wait until the fast comes out for the L92 heads. You should see a decent power increase for sure.
Nice numbers either way though...love that tq, but a 408 should make more power than that...thats why im pretty sure its your intake.
Nice numbers either way though...love that tq, but a 408 should make more power than that...thats why im pretty sure its your intake.
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Dont know how you're coming up with 11.9 comp.......
What is the bad dip in the A/F? Theres a corresponding dip in the power too.
What is the timing set at? Is it building vacuum at the top of the pull?
Can you get a run log to post? I've tuned a couple of them (L92s). LOL. I'd like to think I got a handle on them.
What is the bad dip in the A/F? Theres a corresponding dip in the power too.
What is the timing set at? Is it building vacuum at the top of the pull?
Can you get a run log to post? I've tuned a couple of them (L92s). LOL. I'd like to think I got a handle on them.
I'd also reccomend porting the intake/TB for better gains, go back make more tuning adjustments and hope for the best. If you think you are getting valvefloat you may want to upgrade those springs as well.
-1.8cc valve reliefs, 4.030 bore 4.000 stroke, .040" head gasket, 68cc chambers ~.01" above deck nets around 11.9:1, with my math
edcmat-l1 i dont have a datalog for the dyno pulls, but the tuner isnt done with the car yet till i fix the hydraulic lines, but ill be sure to see if i can get one.
edcmat-l1 i dont have a datalog for the dyno pulls, but the tuner isnt done with the car yet till i fix the hydraulic lines, but ill be sure to see if i can get one.
Dont know how you're coming up with 11.9 comp.......
What is the bad dip in the A/F? Theres a corresponding dip in the power too.
What is the timing set at? Is it building vacuum at the top of the pull?
Can you get a run log to post? I've tuned a couple of them (L92s). LOL. I'd like to think I got a handle on them.
What is the bad dip in the A/F? Theres a corresponding dip in the power too.
What is the timing set at? Is it building vacuum at the top of the pull?
Can you get a run log to post? I've tuned a couple of them (L92s). LOL. I'd like to think I got a handle on them.
~GrannySShifting
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From: Gateway International Raceway
-1.8cc valve reliefs, 4.030 bore 4.000 stroke, .040" head gasket, 68cc chambers ~.01" above deck nets around 11.9:1, with my math
edcmat-l1 i dont have a datalog for the dyno pulls, but the tuner isnt done with the car yet till i fix the hydraulic lines, but ill be sure to see if i can get one.
edcmat-l1 i dont have a datalog for the dyno pulls, but the tuner isnt done with the car yet till i fix the hydraulic lines, but ill be sure to see if i can get one.
I got the same as your calculation... What did you get Edcmat-l1?
might need a catch can in the pcv system, i know theres gotta be a lot of pressure in the crank case with the big gap in the rings .026" AND .022" might be blowing oil through the 98 style pcv. got my master cylinder fixed up, waiting to install for another run.
