feedforward - BlownByTwins

Tuning the Supra’s Boost Control: PID Gains Were Only Part of the Problem

The latest boost-control work on my Supra started with the PID tables. It ended up exposing a problem in the initial wastegate-duty table that PID alone wasn’t dealing with effectively.…

Engine Management Mk4 Supra

Boost Control on the Emtron KV12: Where the Target Really Comes From

How boost is controlled on the Supra's Emtron KV12: a base table that never asks for boost, a user offset that does, a deliberate clamp, and a PID kept on a short lead so the feedforward does the work.

Engine Management Mk4 Supra Tuning

Erratic Shifts and Idle Overfuelling on the 2JZ: Finding a DBW Feed-Forward Fault

Inconsistent torque, delivery and shifts, with nothing obvious in the log. Working outwards from the symptom into the DBW loop, and the arithmetic that showed the integrator was spending its whole authority cancelling a feed-forward error.

Chart of permitted wheel slip against lateral G for three traction control settings, each forming a dome that peaks in a straight line and tapers as cornering load builds

Engine Management Mk4 Supra Tuning

Traction Control on 1,114 whp: Feedforward, PID, and Why It Never Cuts

1,114 whp, 880 lb ft, and a 295 section road tyre on the back. Traction control on this car is not a driver aid. It is the thing that makes…