Drag mode is designed for drag racing where the engine is free revving while waiting for the signal to launch. At this point the engine does not have enough load to allow the turbo to produce full boost. Using this function will enable the turbo to produce extra boost.
When the throttle signal level is ABOVE the pre-set TPS setting AND the engines RPM is ABOVE the pre-set RPM setting AND the boost pressure is below the pre-set Kpa setting the antilag function will be enabled causing the ECU to misfire the ignition in one of 3 patterns. The ignition timing and fuel delivery will also be adjusted according to the selected fuel and ignition trim percentages.
Setting the boost pressure (Turn OFF Above KPA parameter) is the most critical parameter. This also requires very good driver control because the boost is maintained via the amount of throttle opening.
If you would like to launch at 50 Kpa (7Psi) of boost, you would set the Turn OFF Above KPA parameter slightly above 50 Kpa, maybe to 55 Kpa. While in gear, the driver holds the clutch down and revs the engine. Once the engine reaches above the Turn On above RPM parameter and the TPS reaches above the Turn On Above TPS parameter then Antilag will activate causing the boost to build up. By pressing the throttle to correct amount, the drive can maintain boost at the launch level. To launch the car the driver will release the clutch and open the throttle fully. At this point the boost will shoot up above the Turn Off Above KPA parameter causing the antilag to deactivate and allow the boost to build up to the higher preset wastegate level.
Caution: There is a chance of blowing the engine if the driver presses the throttle too far while free-revving the engine allowing the boost to build up above the Turn Off Above KPA parameter. This may cause the engine to over rev. EMS recommends that you use one of the digital inputs connected to a clutch switch to deactivate the antilag system and set the Turn OFF Above KPA parameter to its maximum value. This method will prevent the engine from over revving while the clutch is disengaged.
FUEL TRIM percentage If this parameter is used then the setting should be a positive value (+) to increase the amount of fuel when the antilag function is active. This is normally set between 0 and +3%.
IGN TRIM percentage This setting should be a negative value (-) to retard the ignition timing as far as possible. This is normally set to –100%.
The misfire patterns have been designed to prevent the spark plugs from fowling up.
You cannot retard the ignition beyond the static timing value so try and set the static timing as low as possible.
Stinger 4 instruction manual version 2.0