Plenty of things pull timing out on a Nexus ECU: torque reduction on a shift, launch control, anti-lag, traction control and more. When the correction ends, the timing wants to go straight back to the base value. A sudden jump of many degrees means a sudden jump in torque, and you feel that as a jolt through the driveline or a lurch in traction.
The Attack Rate table limits how quickly ignition timing can move from a retarded value back toward a more advanced one. It's measured in degrees per engine cycle, so a lower number means a slower, smoother return and a higher number means a quicker one. It only governs timing moving in the advancing direction. Its companion table, decay rate, is covered in its own article.
Setting it up
- The table is disabled by default. Enable it only if you have a reason to.
- It can be mapped up to 3D, so you can let timing come back faster in some conditions than in others.
- Start with a moderate rate and check a log that shows ignition timing recovering after a correction. You want it smooth, but not so slow that the engine feels lazy after every shift.
For the bigger picture, see our ignition tuning overview and the torque reduction article.
