do High Torque starters draw more or less current?

[TerryG]

Long story cut short, I need to replace the starter on my RR (again!) as it is over-drawing. It is a high torque motor which turns the engine over nice and quickly (or it did until it broke). Looking at replacements it is claimed that they "use up to 40% less current". Is that gibberish or is a high torque motor genuinely more efficient so requires fewer amps to start than a standard one? My suspicion is they draw the same number of amps but the sales blurb suggests that they start your engine quicker so need to run for less time.

[suffolkpete]

The current drawn by an electric motor increases as it slows down under load, so I would guess that the high torque version doesn't slow down as much and therefore doesn't draw as much current under heavy load, although I can't see how this can be achieved without sacrificing speed, since power and hence the current drawn is a function of torque and speed.. I wish now I'd paid more attention in machines lectures, it's the only part of my 1960s electrical engineering degree that hasn't been rendered obsolete by subsequent developments

[Wicksy]

If your "high torque" starter is of the geared type it will use less amps than the direct drive design. The reason being that the reduction gear ratio of about 4 to 1 and the increased mecanical advantage allows for a smaller motor to be used Put simply, small higher speed motor, slower higher torque pinion and less current to drive it

[TerryG]

Well, it is shiny, new and looks like a motor with a gearbox so we shall see if it is any better than my old one when I fit it tomorrow (snow permitting)

get-it-started.jpg (116.82 KiB) Viewed 1177 times

£277 from ratsport, I hope it isn't money wasted.