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Old 10-28-2013, 06:38 PM   #9 (permalink)
Frank Lee
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Join Date: Jan 2008
Location: up north
Posts: 12,762

Blue - '93 Ford Tempo
Last 3: 27.29 mpg (US)

F150 - '94 Ford F150 XLT 4x4
90 day: 18.5 mpg (US)

Sport Coupe - '92 Ford Tempo GL
Last 3: 69.62 mpg (US)

ShWing! - '82 honda gold wing Interstate
90 day: 33.65 mpg (US)

Moon Unit - '98 Mercury Sable LX Wagon
90 day: 21.24 mpg (US)
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Quote:
Originally Posted by cRiPpLe_rOoStEr View Post
I'm not so excited about the close-ratio gear ratings which have been prevalent in the manual transmissions. No wonder the automatics, which have been retaining wider ratios, are getting their mileage disadvantage reduced.
Me neither. The bias is towards maximum acceleration capability. I skip-shift my 5-speed m/ts, usually 1-3-5 or 2-4-5. As a flatlander with a car that has abundant torque, I could do away with the extra two gearsets and save the weight and loss of transmission efficiency by having a nice 3-speed. Perhaps my desire for only three gears would change if I lived in hill country and/or had a less torquey engine.

Back in the '80s the Ford "High MPG" transmission was a 4-speed, not the 5-speed which was also offered.

Also I think overdrive gearsets lose power transmission efficiency- the reason they work is that the loss is smaller than the engine efficiency gain. I'd like a "straight through" top ratio with no gear meshes paired with an appropriately tall non-hypoid final drive gearset.

By the same token I believe gearsets have improved efficiency the closer they are to 1:1 ratio; another plus for a tall final drive.
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Last edited by Frank Lee; 10-28-2013 at 07:41 PM..
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