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Old 10-09-2008, 04:40 PM   #2
insite
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Join Date: Sep 2004
Location: Atlanta
Posts: 1,820
Quote:
Originally Posted by Frodo
Thanks.

Makes sense: reduce the weight of the flywheel, you lose some rotational momentum, so you're more likely to bog down the engine when starting out. Ditto when you disengage the clutch to shift---low mass, low momentum keeping things spinning, so it's gonna lose revs quickly.

My kid (a budding shade-tree mechanic) found an Excel spread sheat program that calculates HP gains with FW changes. He says he would need to know the weight (OEM and LWF) and the diameter of each as well. I know I'm being lazy, but anyone know these off hand?
you actually need to know the moment of inertia of each FW along with the weight. i ran the calculations awhile back and found that a 2nd gear sweep from 4800 revs to 6800 revs was good for a reduction of 21HP parasitic loss (~21HP gain) if i remember right.

i'll try to find the measurements. i still have an OEM FW; i'll weight it & measure it this weekend.
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