[335stoner]

is it higher or lower than the 4700? I have the ability to change it in XHP and wonder if I should lower or raise it.. it can be changed for each gear..

thinking of going to 4500 to bump the RPM closer to the max torque range??

[BB_cuda]

Always shift at max hp not torque. We specifically had to prove this in ME school.

The question posed was for maximum acceleration, do you shift at max hp or max torque? Max torque way lower in the range.
EDIT: now getting me to remember how I did this is another story. There were partial derivatives involved.

[robnitro]

You want to shift a little past peak hp, in order to have the next gear start closer to peak hp.
The idea is to have the most hp across the range.
Take the approx rpm range between a shift (ex drop of 1000 rpm).
See where on the graph you get the most of the hp curve in a 1000 rpm range. On my vw tdi I had flat hp from 3000-5000, so I could shift at 4k or 5k and get the same power band. On our engines and tunes, there's variation so look at the graph.
Let's say peak hp is at 4000 and drops off past 4700. A good estimation for a 1000rpm spread would be to shift at 4850, going into next gear at 3850... That would give more average hp in that spread than shifting at 4700 and going into 3700...


Torque is not what accelerates you, hp does. Hp is derived from torque anyway. HP= tq (ftlbs) x rpm/5252.

[Owen81]

Have you read this POST?

DWR explains it quite clearly

[DWR]

Ha, better than that, I gave everyone a tool to determine best shift rpm!
You will find the one-size-fits-all answers to this question miss the mark. That's because it all depends on the area under a curve. That means it depends on the shape of the curve and the interception of curves. If all engines had the same shape torque curves, one answer would suffice.

[Needbmwpartzz]

Redline

[335stoner]

i never saw DWR's calculator! wow..