Hi Tab,
Tab Julius wrote:
>
> Regarding wear on the engine, since so many people have mentioned it...
>
> The consensus from people who rebuilt engines for a living was that there
> was no appreciable difference. If anything, sometimes the engines were
> better since they'd been "cleaned out".
>
Good old Consensus, AKA "Everybody Knows." When I find that C or EK
fly in the face of what I consider reasonable analysis, I consult
textbooks & engineering manuals. Consider this: There's a term called
Piston Speed (PS). In the USA it's measured in feet per minute (fpm).
It's easy to calculate: twice the stroke length times rpm over 12. A
rule of thumb is the higher the PS the greater the cylinder (etc) wear.
One of the reasons for short stroke engines is to keep the PS down to an
acceptable level. Has to do with friction losses too. Also volumetric
efficiency, tho that's not germane in this case. Maybe those engine
rebuilders don't know about this stuff.
CR
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