Fix_Until_Broke said:
Is lugging restricted to lower engine (therefore piston) speeds?
I agree its to do with low engine rpm, high load condition and timing.
The ecu does its best to compensate, and does it a lot better than any carburetted, distributor capped gasser engine which are a lot more susceptable to lugging effects.
A diesel engine can handle overload, its part of the fundamental. Example, my Yanmar YSM12, is rated 12HP max on overload, 10 HP continuous, at the same max 3000 rpm. I need that because its in a 5 ton sailboat. On a calm sea at full chat 10 HP is what it runs at spinning the screw merrily. Now start powering into a sea with a few breaking waves on it. The boat charges along and into the face of a wave, which despite its 5 tonnes, slows the boat, and meanwhile the surface of sea water is also travelling with the boat, (a fundamental of wave formation) so at this point in time that screw that was spinning merrily in 5 knots of water is now required to spin against 2 knots of water, thus loading up the propellor blades quite dramatically, the engine responds not by dropping revs, but by using the overload capability, to feed more power in, and maintain rpm. Diesel engines can do this, its a fundamental in their design, gassers dont have the same mechanisms at at all. A gasser engine in the same situation would drop engine rpm, and thus lose power, then attempt a recovery by overfuelling, by which time the wave has moved on, and the rpm and power have been dropped.
cheers.