Quote:
Originally Posted by Eddien123
I wasn't saying a drop in RPM from 3,000 to 2,500 would be bad for economy. But most people assume getting a highway cruise at 1500 will do the trick and it will not. Plus this car isn't even designed to be an economy car so M has no reason to drop the highway revs.
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If I assume "the trick" is significantly better mpg, then dropping the gearing enough to obtain 1500 rpm at cruise (from 3000) will absolutely do the trick. The car most assuredly will be a comparative pig out on the highway with that gearing, but will also most assuredly be much better on fuel, for the reasons already documented.
Your opinion on this is to the contrary, so I'd like you to provide additional proof points to bolster your position, since I've already addressed your point about equal fuel being used at a lower rpm due to the need for more fuel per power stroke. Again, that point doesn't address either friction issues at higher rpm or increased pumping losses.
Bruce
PS - Porsche has addressed the economy issue with a tall seventh gear on the 991 911, so why wouldn't BMW do that.