Actually, if your goal is to accelerate fastest, you should always shift
above the power peak. The idea is to get the maximum area under the power
curve between the shift points. A reasonable "seat of the pants"
approximation is to shift when the acceleration in the lower gear has
fallen to what you will get in the higher gear. This is independent of
displacement or gear ratio.
Since a TR3's gears are not evenly spaced, the correct shift point is
actually different in each gear. IOW, without an OD, you stay in 2nd to a
higher rpm than 1st and 3rd. With an OD, you shift out of 2nd (into 2nd
OD) sooner.
Randall
On Tuesday, July 25, 2000 5:35 PM, Donald H. Locker
[SMTP:dhl@chelseamsl.com] wrote:
>
> 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.
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