Quote:
Originally Posted by JulianEdgar
Ok, you definitely haven't read how throttle stop testing works.
The engine is at a constant throttle. RPM varies inconsequentially The air/fuel ratio is constant. Ignition timing varies inconsequentially.
But look, don't worry about it. The technique works brilliantly - if you can't get your head around it, that's OK.
|
1) If you've altered the drag you've altered the road load horsepower requirement of the vehicle.
2) If the engine is not kept at a constant load, its BSFC will wander to a less efficient 'topographical region' of the engine's 'map.'
3 It doesn't matter if the throttle position, RPM, and stochiometric ratio are constant, you've altered the thermodynamic properties of the engine and they haven't been accounted for.