Quote:
Originally Posted by CanAutM3
I am still on the fence if it has an impact on the optimal shift points though. Intuitively, I don't think it does. But I am not able to demontrate it mathematically...
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OK, I thought about this on the way to work and I've changed my tune. Now I think swamp2 is correct.
Here is how I thought about it: when you change the wheel size on a car, all other things being equal, you'll change the rate of acceleration. When the car's acceleration changes, the rpm acceleration of the engine and transmission reciprocating mass changes. Therefore the inertial loss in the engine and tranny changes and these changes are not constant per gear. The loss is higher in lower (numerical) gears.
Therefore you can affect output power by changing the car's acceleration which means you can affect shift points.
The total power produced by the engine doesn't change but more of it is lost to accelerating the engine and transmission internals when the car accelerates harder.
And when I think back to the discussion, this is what swamp2 has been saying all along. So thanks swamp2, I learned something today that I never knew before!
Pat