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The Crane cam is degreed "straight up," neither advanced nor retarded, and is held in place by a Crane billet roller timing chain. The cam sits in the bearings with a tight .0015-inch clearance (cold) to account for the aluminum block's expanding at twice the rate of an iron block. Compare this to the .0025-inch clearance Urban would run on a cast-iron engine to end up with the same clearance at operating temps. Because of this tolerance, I'll have to take a little time warming up the engine (to go to work!) on those cold Michigan mornings to prevent scuffing a bearing.