Originally Posted by alistairolsen
its not block strength thats the issue in most cases, its the mass of the valvetrain and rotating assy. In lightening this, you reduce the wear life of the engine (how many 100k mile motorbikes do you see?)
If you built a big multicylinder motorbike engine youd be heading for F1 style designs and there is no reason why you couldnt have 15krpm in your car, but it would mean writing off your engine at 20k miles probably lol
i think you are vastly underestimating the life expectancy of these engines
the current f1 engines have to do 2 races but even so, they won't last much beyond 600 miles at 18k rpm, they were lasting 300 miles before the new rules were introduced which dropped the rev limit considerably
don't forget that back in the day they were able to change engines willy nilly so you'd have an engine with a shelf life of about 50 miles but was tuned to fuck just for setting the lap times in qualifiying and then they'd change back to a less periolous engine for the actual race itself
a bike engine might last a while if it had a 15k rev limit but in a car i can't see anything much beyond 9k rpm lasting any considerable length of time, especially not a mass paket produed engine in the likes of a focus etc