hello all... A part of my final year project involves the determination of frictional power of an I.C.Engine(for this we used a 4cyl isuzu si engine) using a typical motoring test(using a 3ph ind motor and the engine was stripped of all its accessories liek alternator water pump), and finding out if there would be a reduction in frictional power if we mounted the engine in diff orientation(horizontal like a flat 4 or a boxer only all cyl were inline). Well we were able to get a reduction of between 9-1.4% reduction in friction with variation in speeds(the % diff reduces with increase in speed). Now to what exactly can we attribute this reduction in fp? Would be extremely grateful if anyone could explain this to me. Thanks.