nuggetino said:Any reason most engines these days have an interference design? More power, fuel efficiency? I went for a subaru 2.2 engine conversion in my van as they have a non-interference design. Always made me wonder why all engines aren't built with this in mind. Heard so many horror stories of timing belts breaking and destroying engines.
better power is derived from close tolerances and timing between valve opening and durations in relation to piston position.
an engine with big tolerances between piston crown and valves wouldnt get the high compression ratio that creates horsepower and combustion efficiency.
you have to have it.
and timing belts are used because they are cheaper to manufacture than chain drive
you might be surprised at the lengths manufacturers go to just to save 0.005 cents on each component