So i just watched a video on the new Camaro which i just bought and was blown away at the 70 hp power loss!!!!! How do they rate a car for 428hp and when you get it dyno it only pulls 357hp???? Is this video wrong or is this true????? Just need a little info.

 

all cars have a loss of hp through the drivetrain. so the hp numbers were probably at the flywheel

 

Advertised h.p. of an engine is at the flywheel, the dyno tests at the wheels. So as nj said, it's due to drivetrain drag. In the neighborhood of +/- 15% loss can be expected, with an automatic. That would adjust the 428 flywheel hp down to 363.8 at the tires, which is right in the ballpark of the dyno test you watched.

 

its going to be far more than 15%, especially through an automatic. Nascars engineers have gotten at best ~18% drivetrain loss, expect to see north of 20% on a street car and in some cases more.

For reference, my car puts down 394whp and the times it runs says it makes north of 600

 

With the car in question, 428 to 357 is a 17% loss. Well within my +/- of 15% estimate.

 

Thanks guys i just figured it would be closer. It is just crazy that the stock 5.0 puts down more on the dyno then we do. But it says they are very underated. Hopefully these boltons will help me get it back up to 420 rwhp.

 

holy crap that sucks. learn something new everyday. Here I've been thinking of foregoing the ZL1 and just gettin an SS and "settling" for 428hp. Now I'm perplexed. So at 17% I guess the ZL1 will be putting down around 481 horses.

 

somewhere around there, there are plenty of things you can do get it to put down more power without touching the motor, namely reducing rotational mass. Lighter wheels, brakes and an aluminum driveshaft are all things that will help you "free" up more of that power that is sucked up in "drivetrain loss"

 

I talked to hennessy they 7k to bring it up to 400hp on a auto. They call it the 475 pack but it puts 500 to the wheels.

 

My 2010 Chevrolet Camaro SS/RS @ Complete Street Performance in West Chester, PA.
Getting a dyno baseline with current bolt-ons before Lunati Cam, Advanced Induction Heads and Kooks Headers installs.

Dynojet Dynamometer

Max Power = 392.99 Max Torque = 382.62
Max Power = 391.46 Max Torque = 372.13
Max Power = 383.11 Max Torque = 373.28