Post your BONE STOCK LS3 dyno numbers...
01-09-2008, 09:10 PM
#82
Race Director
LS3, 475 miles, 6 sp. No modes bone stock base model.
Test done on a Dynapack Chassis Dynaometer.
Base run and tune run on 91 octane.
375.8 rwhp.....383.0 lbft
after tune
398.1 rwhp.....407.1 lbft
Correction method SAE
22.3 rwhp gain and 24.2 lbft gain
AFR was low 11's. After tune 12.4.
Performed at Synergy Motorsports
Thanks Rick
Test done on a Dynapack Chassis Dynaometer.
Base run and tune run on 91 octane.
375.8 rwhp.....383.0 lbft
after tune
398.1 rwhp.....407.1 lbft
Correction method SAE
22.3 rwhp gain and 24.2 lbft gain
AFR was low 11's. After tune 12.4.
Performed at Synergy Motorsports
Thanks Rick
Last edited by Boomer111; 01-09-2008 at 09:14 PM.
01-13-2008, 05:49 PM
#83
Le Mans Master
08-15-2008, 01:10 PM
#86
It is precisely rated because it is SAE CERTIFIED HP. Production engine output must consistently be within 1% of the advertised figure in order to obtain and retain the Certified rating.
http://www.caranddriver.com/features...olution_column
People who think that a fixed percentage (e.g. 17%) can be applied to somehow "convert" drive-wheel HP to flywheel HP don't understand the complexity of the subject. This is one of several good articles I've seen on the subject. As you can see, high HP cars can "lose" less than 10% from the flywheel to the dyno rollers.
The NPP LS3 is rated @ 436 HP. 10% of that is 43.6 HP. 436 - 43.6 = 392.4 HP, which is at the high end of what stock LS3 NPP cars are recording.
http://www.sportcompactcarweb.com/pr...t_4/index.html
"Horsepower Hype--Separating Fact from Fiction
Converting rear-wheel power figures to crank numbers is anything but straight-forward. When translating wheel figures to engine claims, some experts use fixed conversion factors. That is, if a stock 218 rear-wheel hp RX-7 is rated from the factory at 255 crank hp, it must have 17-percent driveline losses. A 284 rear-wheel hp RX-7, then, must be blessed with 332 crank hp. This popular, if somewhat optimistic, correction technique assumes driveline loss is proportionate with engine output. That is, as wheel horsepower increases, driveline loss must also increase commensurably. Some would even disregard stock quotes and apply a standard 20-percent drivetrain loss figure. Using this popular correction factor, we already have a 340-hp monster! Some would vehemently disagree. These folks would tend to use a fixed number to represent driveline loss. In this case, they would believe that all RX-7s are faced with a driveline loss of 37 hp. (255 minus 218). Using this correction method, Project RX-7 produces a more conservative 321 ponies at the crank. All three techniques, (as well as other far more [Ahem.] optimistic methods) have been used at one time or another.
Our friend at Superior Dyno Service, Keith Paulsen, looks at this issue from another perspective. "The first mistake people make is assuming that factory-quoted horsepower figures are accurate," Paulsen states. "Due to marketing hype and year-to-year tuning changes, it's not always accurate to derive drivetrain loss by comparing measured wheel horsepower and factory quotes."
Paulsen also believes that drivetrain losses are neither an absolute percentage nor a fixed number. Instead, he feels the crank-to-wheel relationship is far more beguiling. From his considerable experience, Paulsen suggests that low horsepower (100-200 hp) cars may suffer from as much as 15 to 20 percent of drivetrain loss at the rear wheels. For more powerful cars (200-400 hp), the figure is around 12 to 15 percent. And for mega-powered cars (above 400 hp), the drivetrain losses can reduce to 10 percent or less. What's going on? Getting into the physics behind this complex relationship is worthy of a project in itself. (Engineering editor, Dave Coleman says he's working on it.) For the scope of our project, let's take Paulsen's advice and only compare apples to apples. In our case, our apple is rear-wheel horsepower. So be it. Readers should also note that we made sure that at no time were race fuel, tweaked ignition maps, chilled intercooler, or wastegate trickery used during our dyno testing. We tested our daily driver, not a one-off test mule. Notable was the fact that the five consecutive runs, separated by five minute "cool down" periods, yielded variances of only 1 to 2 hp."
Last edited by harddrivin1le; 08-15-2008 at 01:23 PM.
08-09-2009, 03:51 AM
#90
Safety Car
There is no more underrating or overrating. The LS3 like the LS7 horsepower rating is SAE certified. Meaning that GM is guaranteeing that all the engines of each type, be they LS3 or LS7, will dyno within 1% of one another. There are no ringers, strong ones, weak ones or underrated ones.While the links below refer to the LS7, they can also be extrapolated to the LS3 because both are SAE certified.
http://forums.corvetteforum.com/show...post1562787163
http://forums.corvetteforum.com/show...&postcount=356
http://forums.corvetteforum.com/show...&postcount=371
If its SAE certified, it pretty much is what it is.
Question: Does anyone know what the LS2 horsepower rating is based on the new horsepower "certification"?
08-09-2009, 05:37 AM
#91
Get Some!
08-09-2009, 05:42 AM
#92
Get Some!
As far as I know we don't but as discussed in another thread and on the SAE website, some engines went up in HP and some went down.
08-09-2009, 10:28 AM
#93
Law Dawg Moderator
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