RPM vs. Time to evaluate performance changes?

[CSTR]

Does TunerStudio or Megalog Viewer have a plugin that anables one to calculate torque based on rpm vs time?

I know that GPS and accelerometers have suspect accuracy, but the rate of change in rpm should be an accurate indicator of acceleration. This data could be overlaid in diff logs, or torque could be calculated if tire diameter, weight of car, and gearing is known.

I know that some of the android apps will do this, just wondering if there is a facility for this in TS?

[LT401Vette]

TS and MLV calculate HP and Tq from speed in the registered editions. The calcs are based on speed, so you need some type of speed sensor or a high speed GPS to capture speed from.

[CSTR]

TS and MLV calculate HP and Tq from speed in the registered editions. The calcs are based on speed, so you need some type of speed sensor or a high speed GPS to capture speed from.

Thanks. I have the registered version, I didn't know it could do this.

I think they should offer the ability to convert from RPM to speed. You would need to know the gear ratios and tire size.

[LT401Vette]

In MLV look under:
Calculated Fields --> Optional Fields --> HP MPH
and
Calculated Fields --> Optional Fields --> HP TQ

That does as you want from RPM.

In TS you can set the input source to userSpeedMph, then define userSpeedMph in your custom.ini to derive speed from RPM. Naturally this will only read sane when you are in the right gear.

[Rick Finsta]

You'd also need to know converter slip in an automatic, which would be problematic as the relationship changes relative to the variables you're considering (rpm and torque) over the elapsed time of a pass, and is different in every gear. So no matter what I'd think you need a vehicle speed sensor (or at least an output shaft or driveshaft sensor for differential rpm readings) to get meaningful numbers and at that point you can just use the vehicle speed...

[LT401Vette]

Yes with an auto converter slippage is a big factor. The MLV calcs do have a stall speed entry to make an attempt to deal with that as well. You will need to tweak around with the stall speed setting on your setup.

[CSTR]

This is for a manual.

[iti_uk]

TS and MLV calculate HP and Tq from speed in the registered editions. The calcs are based on speed, so you need some type of speed sensor or a high speed GPS to capture speed from.

Thanks. I have the registered version, I didn't know it could do this.

I think they should offer the ability to convert from RPM to speed. You would need to know the gear ratios and tire size.

Not really. You can derive power purely by knowing the rate of acceleration and the mass of the vehicle. From this, you can apply a rough transmission loss multiplier then take instantaneous RPM into account to calculate engine torque.