For any vehicle and any final drive ratio, in theory, if you really
want max acceleration, you should shift at the horsepower peak RPM.
Because of the gearbox's multiplication of the torque from the engine,
you will have more torque at the tires at the power peak in gear N
than at the torque peak in gear (N+1). Assuming your gearbox is
correctly matched to the engine. It is possible to even want to shift
above the power peak RPM, but not usually below it.
Try the dashboard dyno thingie, if you really want to know. Opinions
are great, but data counts.
Donald.
> Date: Tue, 25 Jul 2000 11:16:15 -0700
> From: John Cowan <jfcowan@pacbell.net>
>
> This is a curiosity question for those of you driving TR-2/3As with
> the 1.991 Liter engine and the 3.7 rear end. I wonder what shift point you
> and the car 'like' when upshifting; i.e., at what RPM do you upshift?
> Shifting at a point just past the shoulder of the torque curve gets
> you the best acceleration, since when you upshift, you then
> drop to just below the shoulder and are in the right position to
> accellerate in the higher gear.
> The torque curve in the shop manual says max torque is118 ft-lbs
> between 2500 and 3700 RPMs. Also, the right point is often discernable by
> feel. I have my own preference, but am interested in the experience of
>others.
> Thanks.
> John Cowan
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