What this table does
With RPM Shift Point Enable switched on in the Transmission Control function, NSP adds the RPM Shift Point table. It works much like the Auto Mode Shift Points table, with two big differences:
- Shifts are triggered by engine RPM, not by the main shift point variable.
- It keeps working when the gear selector is in Manual, so it can act as an automatic upshift and downshift safety net for a driver who's shifting themselves.
It's a special table: its left axis is locked to the RPM Shift Point Axis channel and can't be reassigned like a normal table axis.
Avoid the shift-hunting trap
When the transmission upshifts, engine RPM falls by the ratio between the two gears. If your downshift point for the new gear sits above where RPM lands, the controller sees a downshift condition the instant the upshift finishes, and the car bounces between gears.
Here's a worked example with our own numbers. Say you upshift 2nd to 3rd at 6500 rpm, and the ratio change drops the engine to about 4800 rpm in 3rd. Your 3rd to 2nd downshift point must be comfortably below 4800 rpm. We leave a healthy margin for tire slip and RPM drop variation, then confirm in logs that each upshift lands well above the matching downshift point.
For each gear, multiply the upshift RPM by (next gear ratio divided by current gear ratio). That's roughly where RPM lands. Your downshift point for that gear must sit below it.
Choosing your shift RPM
Most gasoline engines, and nearly every motorsport engine, hold their power well near redline. For those, shifting as late as safely possible is usually quickest.
Engines whose power falls away at the top end are different. Diesels, low-RPM torque engines and restrictor-limited race engines often go faster by shifting earlier. The theory is simple: the ideal upshift is the RPM where power in the current gear equals the power you'll have right after the shift. Finding that point needs your dyno power curve and your gear ratios. Plot power against road speed for each gear, and the ideal shift is where one gear's curve crosses the next.
Related settings
Fine-tune shift feel with Shift Duration, stop unwanted shifts with Shift Inhibit, and check your solenoid mapping in Outputs for Gear.
