Quote:
Originally Posted by Pseud0logik
So either the car is over-rated or it has 17%-18% drivetrain loss. 
I'd like to see more baseline numbers after 500+ miles and an oil change. |
17%-18% driveline loss is appropriate for FR car with manual transmission and an independent rear. In fact, it might be a little high, but that could be a dyno variance. Solid rear axle cars with manual transmissions are in the 12%-15% range. An independent rear or auto will bump that another 2%-5% each.
It's when you start looking at AWD that the numbers really jump since you're nearly doubling the driveline. Subarus will see as much as 26% driveline loss.
Quote:
Originally Posted by Prava
I know the specs say that the car is 200whp at 7000rpm... But I don't entirely understand how a dyno works entirely. Is it a 3rd gear pull to a certain rpm/mph? Can somebody explain it simply? And also, simply why its not pulling towards the 200whp zone rather than 164.7whp?
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The specs aren't whp (wheel horsepower), they are bhp (brake horsepower) which is measured at the crank with a dyno called an engine brake.
It takes power to turn everything connected to the engine, so the more you have connected (transmission, driveshaft, differential, half shafts, and wheels) the more driveline loss you'll see. So whp is a better measurement of the real power seen when driving the car, but bhp sells cars because it's a higher number.