longtubes dyno numbers
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i got my 01 ss dynoed wed at f body central and i got 323 hp and 326 torque. isnt that kinda low? i thought they came stock with 320. this was on a mustang dyno and the only thing on the car is intake, pacesetter headers no cats and lm1? wtf
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F body's were unrated from the factory it's the same LS1 as the vettes. 350 at the fly so about 14% loss to the wheels put our cars to 300wrhp with M6 and auto's lose more about 280wrhp and 290wrhp. With his mods 323 is about right on the mustang dyno and dyno jet it would be about 330 to 340
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yeah dude, the hp ratings that are advertised for cars are their hp at the engine. a dyno measures the hp the car actually puts down to the road. these numbers are usually between 15-20% less than the hp at the flywheel. plus a mustang dyno does show lower numbers than a dynojet, so 323 on a mustang dyno is good for what you've got. in the terms you were thinking, your car would have somewhere around 375 engine hp.
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I don't know where GM got their HP claims b/c it's not what's at the flywheel. Consider that most stock M6's dyno from 290-310 and figure in a 15% drivetrain loss gives you from 340 - 365 flywheel. I think my '99 T/A was rated at like 305HP...I got 311 RWHP just with catback and free mods.
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I don't know where GM got their HP claims b/c it's not what's at the flywheel. Consider that most stock M6's dyno from 290-310 and figure in a 15% drivetrain loss gives you from 340 - 365 flywheel. I think my '99 T/A was rated at like 305HP...I got 311 RWHP just with catback and free mods.
All hp specs are now listed in bhp (brake horse power), this is designated by the ASAE (American Society of Automotive Engineers). This value is taken at the engine crank on an engine dyno.
GM purposely underrated the hp mainly to help reduce the consumer insurance rate which was and is a big incentive to sell more high performace cars.
This trend comes from the late 60's and early 70's when skyrocketing insurance rates killed the muscle car and this practice lives on even today. Another big reason in GM's mind was the fact that the F body is on par with their flagship sportscar; the 'Vette. GM really didn't want it well known that for approx. 20 grand less you could have basically the same performace as their "racehorse".
Its the same as the reasoning in changing the color of the Pontiac CETA from Millenium Yellow to Sunfire Yellow because the 'vette folks claimed it would affect the 'vette sales to have a (so called) corvette color on a T/A.
You've got to look at the overall picture to figure out what time it is.
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Last edited by Weezzer; 06-20-2008 at 07:19 PM.