Lugging isn't necessarily a bad thing, unless it produces preignition- - - -which produces detonation- - - -which destroys pistons, valves, etc. If the engine happens to be running at or near its torque peak while it's being lugged, that produces the best acceleration. A pretty good way to create a "field expedient dyno" is to find a long hill where the vehicle can make stopwatch timed runs at full throttle at various engine speeds and timing settings, without over-revving. Somewhere along the way, a minimum time will be achieved, indicating the best HP/torque compromise has been found.
Jerry
