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Old 08-06-2023, 08:40 AM
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Quote:
Originally Posted by steve25 View Post
A roller chain does not self dampen to the loading and unloading of a cam lobe as 16 valves opens and close, in fact it’s said that the added mass of the rollers themselves when not riding on either gear creates a escalation of vibrations as the rpms go up with the result that the chain beats itself up due to yet a different pitch of vibrations then the cam lobes make.
Also we have not factored in the 17th load of driving a mechanical fuel pump, nor the loading and whatever vibration pitch the oil pump adds to the mix........
PMD engineering included an R&D task to find the cam-crank CL distance for least torsional harmonics. Closer or further CL increased torsional loads on the....camshaft.