if the bock was made strong enough what could it rev to before the actual engine would fall to bit as the honda integra can rev prety high and thats a car just thinking how high four stroke bikes can rev and wondering why the techniques cant be used in a car

 

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

 

it's all about reciprocating mass, the inside of a bike engine is mad, all the components are shaved to fuck-all, and don't forget most bikes have over square engines, ie a very short stroke and a big bore, to aid revs.. Also solid lifters etc etc, but don't forget bikes make fuck all torque either

 

as well as all the above, bikes have a lot less of a job to do, ie not such a weight to lug around, less load.

type-r's dont rev THAT high, 600bhp+ cossies often are made to happily rev to 8.5k, which is about what Type-Rs do anyhow.

thats just down to the fact the ports and cams are wild as fuck to enable it to make power at them revs.

 

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