Quote:
Originally posted by Trevor
Harvey your in depth knowledge of the subject is obvious and appreciated but you have inadvertently left out describing an important factor.
Engine designers use the load available in respect of driven accessories as a means of damping torsional vibrations, particularly in the lower frequencies, as is exhibited in many engine designs, even those of vintage character. Electrical machines provide an excellent facility as do rotary pumps and fans. What is more any accessory driven by means of a flexible belt incorporates an additional damping medium.
The pulley in question drives a load and this load applied via the cushion incorporated in the pulley has greater effect than the inertia created by the weight of the pulley. However I agree with you that doing away with the pulley and integral damper on the basis of restricting inertia, in respect of a stock engine, is completely futile. The mass involved is quite insignificant.
The gullible will always present a lucrative market !!!!
Rergards, Trevor.
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Yes Trev, that is a point. Most used to have the damper weight separate to the accessory pulley. Subaru has it as the driving pulley also, so these must be considered as part of the damper mass.
I agree with it being a pointless mod, when you consider the inertia removed, is very small when you add the flywheel, transmission, drive shafts, differentials, half shafts hubs, disks, wheels and tyres. Then there is the 3500 car mass that has to be accelerated. A few pounds on a 5 " diameter is about 2 tenths of " Sweet Fxxx All"
Harvey.
