[paddy_m]

there is a reason OHV engines can't perform OHC engines, mass. With OHV engines you need pushrods, which add mass to the valve train, these aren't needed in OHC engines. Generally to get more performance out of a given displacement engine, rpms are increased. When rpms are increased with OHV engines, you run into problems controlling the valves because you have a much larger mechanical system, which requires larger springs, pushrods also flex. All of this ends up mattering in a big way. F1 engines have overhead cams for specifically this reason.

[gravitycop]

F1 engines have overhead cams for specifically this reason.

F1 has displacement limits. http://en.wikipedia.org/wiki/Formula_One_regulations#Engine

F1 is not relevant to the world outside racing, where there are no displacement limits. Important engine metrics in the consumer world are size, weight, reliability, repairability, fuel economy, and capex economy.