Mike,
> Charley, most engine wear takes place during start up, when the working
> parts/oil is cold. Once the engine has reached operating temperature,
Sure..
> constant engine speed, wear remains the same irrespective of the engine
> speed. Lower engine speed will result in lower fuel consumption, not
> necessarily wear.
Sorry, not being a mechanic, this just doesn't make sense to me, so
please elaborate. From the overdrive perspective, you're travelling
along the theoretical highway at 4500rpm, you engage overdrive, your
RPMs drop to approx. 3690rpm, fuel economy improves - you are physically
combusting less gas. You are telling us that there is the same amount of
wear occuring at 4500rpm as at 3690rpm? The pistons are travelling at
2625fpm at 4500rpm and 2153fpm at 3690rpm. The pistons are moving up and
down in the bores more times per second at 4500rpm than at 3690rpm. I
don't understand how higher rpms do not accelerate wear in the cylinder
bore, bearings, all moving parts etc.
A question for an Engineer. If you ran a motor at 4500rpm for a period
of time and compared wear to the same motor that had been run at 3700rpm
which would have more wear? Given constants for other operating
conditions etc.
Cheers,
Neil.
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