Quote:
Originally Posted by brian.coombs@hotmail.com  I have designed a new small diameter steel flywheel for my new engine, which is based on a 28oz balance 302, the question is if I reduce the diameter of the flywheel, do I need to increase the balance weight? if so how do I calculate the new weight?
BC |
When you say you have designed a 'new' flywheel do you mean you have machined an existing 28 oz flywheel down to a smaller diameter, if so and you have not touched the counterweight area cast/machined into the flywheel the answer is NO-BUT you should have the 'new' flywheel balanced with the complete crank assy- the reason being that there may have been areas of higher/lower density in the area machined away which will now have caused an imbalance condition from the original factory work.
Now if you have made a new flywheel from scratch and need to attach/machine the counterweight at a smaller distance from the crank centerline then you have to re calculate that weight to suit.
The " 28 oz " is actually 28 oz at a distance of 1" from the crank centerline, so the further out you go the less actual weight you have to attach or remove if you decide to drill holes etc or a combo of both if reqd. From memory I think it goes like this
( DO NOT Quote me, I am not perfect on some of this stuff )............. 28oz @ 1" radius,... 14oz @ 2" radius,... 7oz @ 4" radius,... 3.5oz @ 8" radius. Remember the weight is attached/placed at a specific point in relation to the Flywheel/Crankshaft Flange bolt pattern.
You could also consider going with neutral balance where mallory metal is added to the crank counterweights so that your flywheel and damper can be neutral/non weighted.
Jac Mac