Three Bearing Crank Engine - Centre Bearing Question

[Bob Culver]

The racers here and others have mentioned how they use extreme hugh tensile b.e bolts tightened to exotic torques. It is interesting to reflect that these bolts only handle the upward force of one conrod and piston. Whereas, whilst not pulling on the bolts, the centre bearing handles a goodly proportion of the the same from two pistons together plus the very considerable off centre unbalance of the circular webs and part of the crankpins. Hence the great emphasis placed on rigid crankcases, saviour of the Model T despite bent wire crank. Many cars had alloy crankcases often separate but apparently managed to acheive reasonable rigidity. (Did not succeed with Javelin cars!)