Hardcore GM #2

Sorry for the basic question. I have been told you can take the flywheel horsepower and subtract 15% drivetrain loss or 405hp X 85% equals 344 RWHP. Is this correct? I see people posting all kinds of RWHP numbers that seem ridiculously high for the mods they are making. I just want to see what some real numbers are. I have done some mods: cam, full exhaust, LS6 intake, cool air, dyno & street tune. I'm not seeing the ridiculous numbers posted on here. My $.02


Thanks for helping,


Mark

ASRoff

the LS6 was underrated. the 02 and up usually show 365-375hp to the rear wheels.... LS1tech.com is a better place to find horsepower ratings for stock/ modified combinations...

BTTBSS

Motor has about 50,000 miles. 364 RWHP and 361 RWTQ. Has no name headers with x-pipe cold air intake stock TI muffler and a tune. 72 degrees F. at 650 feet above sea level.

fmvette9

I looked at quite a few stock Z06 dyno results a while back and the majority were in the 352 to 358 whp which seems to put the LS6 in the 405 engine hp range.

Time for a C-5

50hp lost thru the drivetrain is pretty common on a dynojet. A stock LS1 would put down 300 or so hp with a manual. Mustang dynos show lower numbers compared to a dynojet. Do you know on which yours was tuned? Could explain the low #s. I expected higher numbers from mine after heads/cam. I was told the dyno is notoriously stingy and the tuner is conservative. Ultimately it's just a tuning tool.

Hardcore GM #2

Dynojet. I'm not really disappointed with my numbers. I just know some of these people on here are posting ridiculous numbers for mods they have done.

I'm definitely not done with my car. My goal is to beat the new Mustangs and keep up with the new C7.

Thanks,

Mark

Andrew

Mark, what numbers did you make? Also, what cam specs? And no, the LS6 was not underrated, they make 405 chp + or - a few from car to car. I have seen Dyno results all over the place for rwhp. Take them with a grain of salt. Dyno results can be manipulated. Dynos should be used as tuning instruments only, tracking changes on the same dyno with the same parameters to determine power gains or losses from run to run or mod to mod.

Gordy M

Dyno numbers, like Andrew said, can be all over the place, how accurate the dyno numbers can be is determined by how the calibrations for temperature, atmospheric conditions and whether it was a load bearing or not, etc. When the Z06 for 2002 was introduced, our club had the engine chief for the project give us a talk and he mentioned the C5 driveline was about a 12% loss and the Z06 engine was consistently 405 to 408 hp out of the factory. He went into how the PCM was tested to keep the power levels so consistent at that time and most were right at 405 hp.

fmvette9

Thanks for the GM engineer's comments. I wondered what modern manufacturing hp tolerances were. I once read one members account of getting his stock Z06 dynoed at 357 whp. A second stock Z came in shortly after and dynoed 356. These numbers are consistent with 405 engine hp with 12 percent drivetrain loss.

93Polo

345-355rwhp is the norm.