What this table does
While the pit lane speed limiter is active, the Nexus applies this correction to ignition timing. It is an offset, not a replacement: whatever timing the ECU has already worked out from the base map and every other correction, this value is added on top.
- A negative value retards timing and cuts power. This is what almost everyone uses.
- A positive value advances timing.
A worked example
Say the engine would be running 25 degrees BTDC at that moment after all other corrections. If you set -8 in this table, the output timing becomes 17 degrees BTDC while the limiter is on. Turn the limiter off and it goes straight back to 25.
How we set it
Retarding timing reduces torque gradually, so the car creeps along at pit speed more smoothly than with fuel or spark cut alone. Start with a modest amount of retard and increase it in small steps until the car holds speed without surging. Keep an eye on exhaust temperature, since heavily retarded timing puts more heat into the exhaust, and don't sit in the limiter longer than necessary.
This table works alongside the fuel correction and, on drive-by-wire cars, the DBW throttle max. The button itself is covered in pit lane limiter wiring.
