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It’s a special mode we developed for the supercharged Lotus (2ZZ-GE).
The inlet path goes
Air filter -> throttle body -> supercharger -> pipework -> intercooler -> pipework -> inlet manifold -> engine
So when you close the throttle, there’s a large volume of air that the engine has to “eat through”. So it keeps making torque for a long time after you close the throttle.
On light throttle / cruising that’s OK, but if you’re at WOT, and you put your foot on the clutch to change gears, the engine revs up by about 1000 – 1500 RPM because of all this air, even though the throttle is closed.
So the ECU has some tricks to do fuel cuts / ignition cuts, but the timing and severity is based on the RPM and MAP before you closed the throttle, so that it’s smooth to drive slowly, but when you’re racing you don’t get bad RPM flaring when you change gears.
I say: don’t use it unless you’re doing a supercharged engine with an intercooler and the throttle body before the supercharger.