I do not for a second deny that the smaller main bearing diameter on a 340 crank produces less friction than the main diameter of a 360 crank, however, I have never ever seen, read, heard, witnessed on a dyno chart any factual information that makes this a relevant statement........at what HP level, at what rpm does this become relevant?? When I see this statement put up in discussions of the merits of building a 340 based engine over a 360 it is to me IMHOP very much akin to spending the OP's money...he already has the block, help him find pistons and rings for a 4.1 inch bore, that would be alot more meaningful than the suggestions for going to a 4 inch stroke crank
