[dennyt]

I wonder which is greater - connecting rod forces before the oil pressure comes up (very low load, just compression), or the radial load from the starter pinion gear? What I'm getting at is, would hybrid systems with electric motors coaxial with the crankshaft avoid a major component of startup wear, by eliminating the pinion gear load on the crank bearings?

A quick calculation for my car: 92mm bore = 10.3 square inches, at 170psi (last time I checked compression) that's 1750 lbs on the connecting rod. I don't have my starter motor torque & pinion diameter handy...