|
...yep, that's another one, but there are two problems:
...first, we seldom know the Engine Brake Specific Fuel Consumption (BSFC: gal/hr-hp) for our engines; in fact, this is one parameter that we're usually actually LOOKING for most of the time. If you have a BSFC chart for your engines, consider yourself VERY lucky!
...second, we also don't know what the actual Driveline Horsepower (HP) losses are, although the commonly used values of 10-15% for manual transmission and 15%-20% for automatics are pretty close; with FWD being slightly worse than RWD.
...also, I have no idea why he asks for tire pressure (PSI), since it's NOT used in any of the equations he shows.
...a good "Rule-of-Thumb" to remember: at about 50-55 MPH, the roadload (Roll: drivetrain + tires) loss typically "equals" the aerodymanic (Aero) loss.
Last edited by gone-ot; 07-07-2011 at 10:37 PM..
|