Quote:
Originally Posted by Gene F
Because of no oil feed? Ya know O/D saves engines.
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Not because of oil starvation, because of the spidery Model A crank shafts whips and twist a lot. As someone recently said It's tough being a middle main bearing. There are changes that can be made to improve that bearing's life. Things like counterweights on the crank, pressure oil feed to the bearing, harmonic balancer. And let's not forget the driver's style/ability.
You are correct about O/D saving engines. They reduce the revs, hence the amount of punishment meted out to the bearings. I was referring to a standard engine and driveline being pushed along at 60 mph. I have an engine I built 11 years ago that has done about 75,000 miles, mostly at 50 mph with O/D. It has insert bearings, pressure oil feed to the middle bearing (25psi), counter weights, 6:1headnad oil and air filters. It is still going just about as well as it ever did.