Quote Originally Posted by Steve Boyd View Post
Sounds simple but the crankcase and cylinder head also expand so you've got to get the rod+piston crown height to expand by 0.4 mm more than the expansion of the crankcase+head. The problem here is that aluminium alloys, typically used in crankcases expand by roughly twice as much as the steels typically used in conrods for the same temperature rise. It might actually be easier to use an alloy steel for the crankcase and reduce that expansion rather than try to increase the expansion of the rod+piston.
I've had an even better idea!
You make the crakshaft out of something that expands a lot. That'll give you more compression plus it'll increase the stroke so the capacity goes up as well. Double whammy!