These are the limits as tested and printed in the GM build book. This is verbatum from the build book itself.
L61 Rods/Pistons - 250hp
Spark Plugs - 300hp
Fuel Injectors - 300hp
Fuel Pump - 300hp
Sleeves - 400hp
Head Gasket - 500hp
Crank - 500hp
Combustion Chamber Seal - 600hp
Exhaust Rocker Arm - 700hp
21mm wrist pin - 700hp
MLS Head Gasket - 800hp
Head Casting - 900hp
Block Casting - 1000hp
Beyond any of that you are getting a tad rediculous. Those are the main ones that seem to come up quite often in discusion though. A few of these I have personal doubts on. I know HRC had issues with the head gaskets around the 500hp mark. Which leads to the question. Is it wheel horsepower or flywheel horsepower the breaking point on these parts? Hope this helps some of the younger guys with some of the questions of "I wanna do xxx, can my motor take it?"
Keep in mind these are averages from many tests that GM performed. Some went higher than this, others lower.
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4 Cams...32 Valves...5 Liters...This Could Get Fun!
my guess its fly wheel hp
Im a Xbox 360 fanboy...and damn proud of it!!
I strongly disagree on the pump and sleeves.. my stock pump was running 750cc injectors at 18 psi on the built motor which dynod just a tad under 360 whp...
the stock sleeves are stronger then 400 hp
LE61T PTE6262 Powered 
Is there anything in the book about valvetrain hp?
ie valves, rockers. lifters, springs?
Borderlin3 wrote:Is there anything in the book about valvetrain hp?
ie valves, rockers. lifters, springs?
Wow.
You dont replace valvetrain components due to horsepower. You replace them due to other mods(IE, higher lift cams require stronger valvesprings) and the others you replace to gain efficiency.
Edited 2 time(s). Last edited Sunday, February 15, 2009 9:24 PM
Trevor Mullins wrote:
kind of like a screwed up kids sing along
pete the anal monkey lived in my bum..............
best epiosode of barney ever lol
So you can have a 500hp car and not replace anything on the valvetrain? and nothing will break?
Depends on the engine, LSx series, sure. But on a 4-cylinder your not going to reach the 500hp mark without doing head work to improve the efficieny.
Trevor Mullins wrote:
kind of like a screwed up kids sing along
pete the anal monkey lived in my bum..............
best epiosode of barney ever lol
so its something that is necessary to do. I just asked it the wrong way, I was gonna add to my original post about maybe how high you want your rpm's among other things, but I didnt want to waste a post. oh well now ive used two.
headwork and valvetrain upgrades are a must for high horsepower
Built&Boosted moar
04 Cavalier Turbo r.i.p my baby
2nd place 2009 GM tuner bash qwick 8--holla
The book doesn't mention upgrading valvetrain due to hp, but it references other things for rpm...
Valve Springs - 7000rpm
Balance Shafts - 7500rpm
Oil Pump - Extended Time on Rev Limiter (2 step)
As I stated these are not finite magic numbers, it's just in that range you could experience some pretty catastrophic failure.
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4 Cams...32 Valves...5 Liters...This Could Get Fun!
curt, by chance know the stock cam specs? duration/lift and all that jazz. im cuttin some mad tyte custum camz yo..i had it all written down..i have lost my black specs book
Built&Boosted moar
04 Cavalier Turbo r.i.p my baby
2nd place 2009 GM tuner bash qwick 8--holla
HMMMMM I wonder how he knows that tid bit of info on the oil pump LOL
Just for you Matt...
Intake Cam Peak Lift - 5.9804mm
Intake Valve Peak Lift - 10.0795mm
Intake Valve Timing - 116*
Intake Duration @ 1mm - 198.4*
Intake Valve area @ 1mm lash - 1112.9mm squared
Exhaust Cam Peak Lift - 5.9752mm
Exhaust Valve Peak Lift - 10.0792 mm
Exhaust Valve Timing - -108* (thats negative)
Exhaust Duration @ 1mm lash - 193.3*
Exhaust Valve area @ 1mm lash - 1078mm squared
Hope this helps.
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4 Cams...32 Valves...5 Liters...This Could Get Fun!
Piston and rod numbers are way off as well.
FU Tuning
Again I say, if you want to roll the dice above those numbers be my guest. I've had a stock eco hold on pretty far as well, but I've seen more break than not.
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4 Cams...32 Valves...5 Liters...This Could Get Fun!
Skunk wrote:Just for you Matt...
Intake Cam Peak Lift - 5.9804mm
Intake Valve Peak Lift - 10.0795mm
Intake Valve Timing - 116*
Intake Duration @ 1mm - 198.4*
Intake Valve area @ 1mm lash - 1112.9mm squared
Exhaust Cam Peak Lift - 5.9752mm
Exhaust Valve Peak Lift - 10.0792 mm
Exhaust Valve Timing - -108* (thats negative)
Exhaust Duration @ 1mm lash - 193.3*
Exhaust Valve area @ 1mm lash - 1078mm squared
Hope this helps.
absolutely does, exactly what i needed.. thank you..
Built&Boosted moar
04 Cavalier Turbo r.i.p my baby
2nd place 2009 GM tuner bash qwick 8--holla
In the build book didn't they start out using N20? (rather than turbocharging) and after it hit some limits they boosted them to make those higher power numbers? and i would assume that's from the crank not the wheels. GMPP/Roush probably had the motors on the dyno and did several stress tests in a controlled environment rather than drop the engines in cars and dyno run them to figure out WHP..
Skunk wrote:Again I say, if you want to roll the dice above those numbers be my guest. I've had a stock eco hold on pretty far as well, but I've seen more break than not.
The numbers I have seen them hold at and the time frame tells me different. Yes many have blown up before those numbers. Seeing how much of a roll tuning plays in this, I know of a few that I would bet tuning was a issue.
FU Tuning
Am I the only one who noticed this?
Fuel Injectors - 300hp
Are they talking about the Supercharger kit's injectors?
Admiral Jedi wrote:Am I the only one who noticed this?
Fuel Injectors - 300hp
Are they talking about the Supercharger kit's injectors?
I was just about to post that as well...LOL
Something wrong there.
For nitrous, the nitrous kit adds fuel also.
(Tom) S/C Fire wrote:For nitrous, the nitrous kit adds fuel also.
I'm pretty sure GM used a dry nitrous kit on their eco when they were testing it, it's been a while since I've looked at the build book but I think I'm correct.
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