Calculating Crank HP from RWHP

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Apr 21, 2005 | 09:09 PM

DaveGS4

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Calculating Crank HP from RWHP

My brain is mush tonight and I need to calculate crank HP from a RWHP quote. Anybody tell me the forumula?

I've done it before but can't find my XLS... something like 1-drivetrainloss% * RWHP/100

I assume the same forumla will work for RWTQ?

Googled and can't find what I need... any ideas?

Apr 21, 2005 | 09:21 PM

Neo

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From: SoCal

Isn't it

hp = rwhp / (1 - dtl)

where dtl = drivetrain loss percentage, i.e. 25% loss = 0.25dtl

I am not sure if there is something that takes more variables into account but this is what I've been doing for approximations.

Last edited by Neo; Apr 21, 2005 at 09:55 PM.

Apr 21, 2005 | 09:27 PM

DaveGS4

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From: North Carolina

Quote:

Originally Posted by Neo

Isn't it

hp = rwhp / (1 - dtl)

where drl = drivetrain loss percentage, i.e. 25% loss = 0.25dtl

I am not sure if there is something that takes more variables into account but this is what I've been doing for approximations.

That's it, thanks!

Apr 21, 2005 | 10:07 PM

Inabj2

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From: Arizona

I like to be extremely conservative and use 15 percent drivetrain loss... Thats right hahaha I would of rated an auto sc300 at 180 hp instead of 225 hp haha. Im sure for some cars like the sc300 its power train loss is much greater, but eh ...