Rather, it appears fairly constant considering the exceptionally high acceleration observed at low speeds in my results.
I’m curious why such a difference has occurred…
I agree that the developers modeled clutch operation correctly in terms of output torque.
(Though not in engine rev, which should also be constant. But I think it was necessary to make engine sound more realistic.)
Yeah I am slightly amused by the fact that acceleration is about 80% of the max in 8th gear, when starting. I guess this is then modelling torque converters as they say.
I reviewed my old experiment results, and I came to believe that the developers had correctly modelled gear opearations and output characteristics.
What puzzles me now is the reason why they can’t introduce torque converters.
It seems very simple: just replace the current torque curve (orange) with the green curve.
The torque converter is assumed to have a lock-up clutch, a stall torque ratio of 2 and an efficiency of 70%. The maximum transmitted power must be adjusted so that it does not exceed 100%, taking advantage of the fact that, in general, the higher the stall torque ratio, the lower the efficiency.
To better understand the differences between engine types, and the variations within each type, I think it would be helpful to gather torque curves across a wide range of engines, including those used in civilian applications.
Actually, I believe the torque converter is used in every gear.
For example, the 900-T transmission used in the M18 Hellcat and M26 Pershing, as well as the Allison CD-500-3 used in the M41 Walker Bulldog, operate this way.
I didn’t know that — thanks for the correction!
I had imagined the lock-up clutch would engage whenever the converter output torque is (or is expected to be) lower than the input torque, regardless of the gear, as that seemed like it would give the best performance.
I think I should gather information on lock-up clutch operations along with other characteristics of historical torque converters too.
From an implementation standpoint, the torque characteristics can be just switched between with and without the converter, so torque multiplication can be limited to some gears if needed.
This example uses a naturally aspirated petrol engine and a 900-T torque converter. The torque curve with the converter is assumed to be pre-calculated, but how it’s defined is up to the devs.
Instead of “torque converter type” you could specify the multiplier, since the “curve” for each converter is practically identical with a different gradient depending on the multiplier.