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Old 11-06-2020, 07:14 AM   #44 (permalink)
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ND Miata - '15 Mazda MX-5 Special Package
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My thought is that if it can stay in high gear all the time, and doesn't need middle gears for normal driving, such a car has too many low or middle gears and not enough high gears. A taller top gear will always improve economy, up to the point you can't stay in it.

I could use a 7th or even an 8th gear in my car, spaced as far apart as 6th is from 5th. 2nd accelerates at the limit of traction up to around 80mph, 3rd drops into the middle of the power band for passing at highway speeds (if I wanted to do such a thing). 6th is very tall compared with most 4 cylinder vehicles, but I find I don't need to downshift from 6th even climbing steep grades with a trailer full of concrete and construction debris behind my car. It will "high idle" the car up to 50mph on a cold morning in 6th.

So maybe the issue is too much engine, rather than gearing.
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