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post #14 of (permalink) Old 06-06-2014
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Originally Posted by daustin View Post
I don't think a percentage is an accurate rule of thumb for parasitic loss. Say you have an engine with 500 hp in a car and take that 15% parasitic loss, you have 425 to the wheels (75 hp loss). Now say you have a 1,000hp engine in the same car; taking that same 15%, you would have 850 to the wheels (150 hp loss). How did the same drivetrain just take 75 more hp to spin?

Sent from App
Originally Posted by daustin View Post
All I'm saying is that all things being the same, a percentage is not a good rule of thumb for parasitic loss.

Sent from App
This is a good question and I dont think I have a solid answer. But what I can say is that a 1000 hp car and a 500 hp car wont have the same clutch an driveline (at least not for long). So as the other poster here said, perhaps a heavier duty trans needed for a 1000 hp car eats more power to turn than one fitted to a 500 hp car.

But in general is you multiply a car's advertised HP by .85, you will come pretty close to what it lays down on the dyno, rwhp wise.

2011 Mustang GT M6 3.31s

Matt HONEYCUTT Tune, Lethal Off-Road X, GT500 axlebacks, J&M LCAs, UPR UCA, Whiteline LCA relocation brackets, Eibach Pro-Kit Springs, Koni STR.T shocks/struts, GT500 strut mounts, SR Strut Tower Brace

Best 1/4 E/T (05/18/14 MIR - no tune, X-pipe, or UCA): 12.920 @ 109.40 mph (2.059 60ft)
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