Horse power estimate

[topher5150]

What is the most accurate way to estimate the horse power at the engine using the numbers from the rear wheel dyno.

 

[the1andonlyGR81]

from what i understand an you lose some where between 60-70 hp depending on automatic or standard, auto being more

 

[chris2523]

What is the most accurate way to estimate the horse power at the engine using the numbers from the rear wheel dyno.

uh. by pulling the engine, strapping it to an engine dyno, and seeing what the difference is.

there really isn't a way to accurately estimate flywheel hp from wheel hp.

i've seen all kinds of numbers relating to drivetrain loss, and 20% or so seems reasonable.

 

[topher5150]

uh. by pulling the engine, strapping it to an engine dyno, and seeing what the difference is.

there really isn't a way to accurately estimate flywheel hp from wheel hp.

i've seen all kinds of numbers relating to drivetrain loss, and 20% or so seems reasonable.

That's what they were telling me at the dyno, I was wondering if there was a specific formula for our drive trains

 

[Moes8]

That's what they were telling me at the dyno, I was wondering if there was a specific formula for our drive trains

nope,it all guesstimation.

newer automatics claim 12-15% loss, ours 20-25%

manuals ~10%

 

[Right on the Mark]

Just use the %# that comes out for our cars stock and input that drivetrain loss % into your RWHP #'s. Our cars come with 280 and 290hp crank stock hp and average RWHP I heard on these are 220-225hp.

 

[topher5150]

Just use the %# that comes out for our cars stock and input that drivetrain loss % into your RWHP #'s. Our cars come with 280 and 290hp crank stock hp and average RWHP I heard on these are 220-225hp.

So according to the run at the shop, with corrections, 253hp at the wheels

http://www.cardomain.com/ride/2560418/1998-lincoln-mark-viii/page-6

 

[MediumD]

Just use the %# that comes out for our cars stock and input that drivetrain loss % into your RWHP #'s. Our cars come with 280 and 290hp crank stock hp and average RWHP I heard on these are 220-225hp.

I say ignore crank HP altogether, because nobody in the performance world really cares anyway. Ford pretty much made up those HP numbers, considering my 280hp Mark did 20rwhp more than my friends 290hp Mark with the same mods..

 

[Buckeye68]

If you are trying to figure exactly how much flywheel hp you make and are worried about exactly what % is lost then you don't make enough

 

[the1andonlyGR81]

exactly