Yeah - few glaring holes in stuff above -
Abba is that the right way round ? 280HP at rear wheels for me, thats 209kW at the wheels. I reckon I got a damn site more than 209HP at the flywheel. Thats only 177kW
The other way round is still misleading - 280hp at wheels may be closer to 280kW at the engine.
i think everyone is making assumptions on losses scaling. They don't.
Percentages can not work in calculating losses. Percentiles are proportional, lossess are fixed plus a small amount of variation due to things like oil hysteresis etc, Friction losses remain roughly fixed. Your alternator may take 2HP to drive on a 200kW engine. If you use the same alternator on a 300HP engine it still takes 2HP to drive it - not 1% which is 3HP.
Follow me ?
ANyway the only way you can use % is as a cross check for relative losses.
Stock Ecotec
147kW Flywheel
Approx 119 at wheels
Losses = 28Kw (19%)
Flywheel Torque = 304Nm at 3600
Rear wheel derived torque = 559 at 3600, which gives a calculated flywheel equivalent of 242Nm or losses of 62Nm or 20.4%.
Losses are relatively close so the numbers are relatively accurate.
Looking at my Dyno results - attached, you can see that the RWKW = 209 (or 280HP) my driveline looses will be similair to stock, maybe a little less as gearbox is modified, so expecting losses of 25kW, my engine kW islikeley to be 234kw.
Apply same losses calc to torque, remembering 3,7 gear ratio, means flywheel equivalent torque, before losses is about 487Nm. (1351 /3, * 4 , / 3.7). Add about 55nM torque for losses and actual engine torque is likeley to be 542Nm.
I Estimate my engine results as 234kW and peak torque of 540Nm. Seems pretty fair really.