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Old 11-05-2013, 08:33 AM   #12 (permalink)
serialk11r
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spyder2 - '00 Toyota MR2 Spyder
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I'm quite certain they just use the 15-25-40 shift points. My car weighs under 1 ton and has a puzzling 22mpg city rating. The Lotus Elise I think is rated 21 and that thing is another 200 pounds lighter and has a 6 speed transmission with 5% higher revs in 1st gear. Same with the Celica GT-S, which has the same drivetrain more or less (lower mpg rating all around despite more gears and an engine that's within 2% of the same efficiency).

One day I had Torque up on my phone while in heavy traffic and noticed that rolling in 1st gear my fuel economy was typically a bit under 20 mpg, and decreases substantially past 3000rpm. In 2nd, it's in the high 20s, and in 3rd it's in the low 30s. Seeing that the whole city test happens essentially in gears 1-3, basically what's going on is that they're getting maybe mid 20s steady state and then lose some gas mileage to decelerating and accelerating, and you arrive at your low 20s.

If they just shifted at 2500rpm instead (that would be like, 12-20-27) there would be no way to get under 25mpg in this car.

Last edited by serialk11r; 11-05-2013 at 08:50 AM..
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