but the crank and rods will fail because they were not balanced for such high rpms.
Most all new engines these days are balanced pretty well straight from the factory. Mainly because of better manufacturing.


On a pure race engine, everything needs to be taken into consideration, but on most street motors some things are not as important as others. Like I had been saying above, I would probably be more worried about rod angle, compression, and detonation; over R/S ratio. R/S ratio would be more heavily considered in an engine that lives in the higher rpms all day long.


If piston speed was so import to longivity, then the Formula 1 guys probably would'nt be running their motors as high as 20,000 rpms.