My 1000th post here!! Now, why are these Japanese engines losing HP?!

[Kewl X5]

Those sneaky Japanese car company. What a joke....For years, they have been "over-rating" their HP figures to sell more cars. Now, I understand why when I test drive some Japanese cars/SUV that supposedly has more HP than the competing BMWs that the Japanese cars feel slow, dull, and boring.

I'm sure everyone has heard about how Mazda how to "readjust" their HP figures on their Miata. Now, Acura and Lexus/Toyota have to do the same.

How can the same engine in the Acura TL go from 270 hp to 258 hp? Heh heh....Even almighty Lexus/Toyota had to re-rate their engine's HP and of course, they all were lower than originally advertised.

Check out this article....
Japanese HP misrated

Missing Horses
Steve Kichen

For years auto scribes have questioned why Japanese V-6s, such as the 270 horsepower motor in the 2005 Acura TL sedan, seemed more powerful than many American V-8s. Now we have some answers. For 2006, Acura claims only 258 hp for the TL's 3.2-liter V-6.

It is not $3-per-gallon gasoline or a retreat from the industry's ongoing horsepower race behind the revised statistics. Acura and other automakers had to restate power ratings in order to conform to a new standard promoted by the Society of Automotive Engineers, a professional technical organization.

"The committee took a look at the existing horsepower standard and found areas open to interpretation," says SAE spokesperson Gary Pollak. Under the previous documentation, companies had more latitude in the testing process to select fuel grades, fiddle with electronic control units or exclude accessories like power steering. "The new standard has no ambiguities," says Pollak.

Nameplates such as Acura and the Lexus division of Toyota Motor (nyse: TM - news - people ) have quietly restated figures on a number of models. For 2006, the high-end Lexus LS V-8 sedan, the 430, for example, drops to 283 horsepower from 290, while the V-6 in the Lexus RX 330 fell to 223 hp from 230. In contrast, numbers went up a bit for some motors from Pontiac and Buick.

SAE added another twist: voluntary outside verification of horsepower tests. So far, only General Motors (nyse: GM - news - people ) and DaimlerChrysler (nyse: DCX - news - people ) have taken this extra step--at least on a few engines. Some GM engines went down in advertised power. But under the new standard the horsepower promised in the new super Corvette motor, the LS7, went up to 505 from 500.

[Thunder22]

the new C6Z06 went from 500 to 505 with the new formula.

[vinuneuro]

Is it a different formula from the previous? or was there not a formula before.

[Thunder22]

it's a new formula.

[Thunder22]

GM Is First To Certify Horsepower and Torque Under New SAE Test Procedure

Corvette Z06 now rated at 505 horsepower

Detroit - General Motors has become the first manufacturer to certify its horsepower and torque rating using the new Society of Automotive Engineers (SAE) test procedure J2723. The 7.0L LS7 engine for the 2006 Corvette Z06 is the first to be certified under the new test procedure at 505 horsepower @ 6300 rpm and 470 lb-ft @ 4800 rpm.

"The new voluntary SAE power and torque certification procedure ensures fair, accurate ratings for horsepower and torque as it uses third-party certification," said Jim Queen, GM vice president, global engineering and the general chair for the 2005 SAE World Congress. "SAE technical standards level the playing field and this certification procedure is just the latest example of the value SAE has offered over the past century."

"We're very proud to be the first to certify engines with the new procedure and pleased with the LS7 certification results," said Tom Stephens, group vice president of GM Powertrain. "Going forward, GM will certify its engines to the new procedure as we want customers to have accurate information when they make a purchase decision. GM encourages all manufacturers to do the same."

[vinuneuro]

If it's simply a new formula that equates to GM's power figures going up and the Japanese going down, what warrants it as better? If the two formulas had been seuqentially interchanged, the Japanese would be making a little more power now. Regardless of which formula was used first, etc, how do we know either one is better than the other?

[Wagner]

That's why I'm a firm believer in a dyno run of your vehicle before you claim power. For the life of me I have never understood why the auto industry showed flywheel horsepower anyway, it's a useless figure. All generic auto HP figures should be at the wheels. That is a true figure.

That's why my Z putting 263 to the ground makes me happy haha

[vinuneuro]

Originally Posted by WagnerX5

That's why I'm a firm believer in a dyno run of your vehicle before you claim power. For the life of me I have never understood why the auto industry showed flywheel horsepower anyway, it's a useless figure. All generic auto HP figures should be at the wheels. That is a true figure.

That's why my Z putting 263 to the ground makes me happy haha

I couldn't agree more. I always wondered this too. A lot of manufacturers don't know shit about drivetrain, and lose a lot of power there.

[Thunder22]

Originally Posted by vinuneuro

If it's simply a new formula that equates to GM's power figures going up and the Japanese going down, what warrants it as better? If the two formulas had been seuqentially interchanged, the Japanese would be making a little more power now. Regardless of which formula was used first, etc, how do we know either one is better than the other?

The new formula is the more accurate and leaves no window for fudging (as the japanese mfg's do) because the results are verified by a 3rd party.

[statdoc]

Originally Posted by WagnerX5

That's why my Z putting 263 to the ground makes me happy haha

Thought you were selling the Z? Selling your happiness?