Why is it that a Infiniti claims that the G37 Horsepower is rated at 330-HP, but people dyno's their G37 and their peak HP is around 290?

 

Manufacturers horsepower ratings are estimated ratings of engine horsepower. A dyno HP number is actual horsepower rating of the chassis which incorporates drivetrain losses. Many manufacturers estimate their engine horsepower optimistically, while a few actually underrate their engine's horsepower output for various reasons.

 

O, ok thanks Betty!