tranceminister

Is there any way to approximate crank horsepower without having your engine on an engine dyno? Is there a certain percentage lost through the drivetrain, and other parts that is a "standard" to calculating crank horsepower? Just something I was thinking about. I see alot of people giving their dyno numbers and at times will give an estimate of crank HP too. I just want to know how they estimate that figure.

hotrex

isnt it a 15% drivetrain loss?/?

Bone1

whp readout of a dynojet is about a 15% loss.

118 whp * 1.15 = 135.7 hp

hotrex

i crank mad hps in my pants yo...

tranceminister

Really josh? I don't want to know where the torque comes from :P Thanks for the info Mista Bone, that's about what I figured it would be. About a 15% loss.

SpankedYA!

15% is standard but not applicable on all vehicles. loss of a standard transaxle vs auto rear wheel drive? Yeah different.

tranceminister

Yup, your right Dave. Say, an all wheel drive vehichle would be a bit more I would think.

hotrex

yeah bout 22 percent.... ***** wrx

tranceminister

hey I could have been talking about an Audi or maybe a Volkswagon. Perhaps a Porche? I wasn't specifically relating to Honda's but it's good to know.

Ondonti

fwd manual cars can get as low as 12% drivetrain loss, auto trannies can ben arond 15-18% on the VERY low side.

Many awd cars can be as high as 35% drivetrain loss. Thus explaining why a wrx cant beat a 150 fwhp car on the freeway if that car makes torque.