GT-R Factory Launch Control
GT-R ProECU Tuning Guide: Factory Launch Control
This guide covers the factory launch control. For information on the RaceROM Launch Control refer to GT-R RaceROM Launch Control, Rolling Launch and BOTL
Introduction
The Nissan GTR has a built in factory Launch Control Mode, when conditions are correct this will deliver an extremely effective launch condition. When entering the special mode the throttle butterfly will react quickly providing a burst of Engine Torque which will load the transmission and drivetrain for a blistering launch condition.
This launch condition is often mistaken and confused for the typical ‘stall test’ launch that can be induced by on most Auto gearboxes models at the traffic lights (left foot on the Brake, Accel pedal to the floor and wait for the lights to change). This low torque/low RPM slipping convertor/clutch launch is not the same or nearly as aggressive as the special Launch Control Mode, though this type of launch is still very effective on the GTR when used.
From 2008 to 2013 each new version of the GTR had a revised launch behaviour, and these have been broadly categorised as LC1 to LC5 by EcuTek and its competitors. The LCx nomenclature is not official Nissan terminology, although some Nissan dealers will understand the term. There appear to be five different LC strategies, however there are not 5 distinct versions of TCM rom with different LC strategies, some ROMs use the same strategy with different map an data values resulting in different behaviour for the drive, some LC versions the result of different ECM maps.
Table of Contents
- 1 GT-R ProECU Tuning Guide: Factory Launch Control
- 2 Introduction
- 3 Table of Contents
Supplemental Content
Platform Specific
- GT-R ProECU Tuning Guide
- GT-R RaceROM Tuning Guide
- Nissan GT-R Diagnostics Tools
- GT-R DTC List
- Nissan GT-R Fuel Injector Installation
- GTR - Live Tuning
- GTR Dwell Time
- GTR OEM Transient Fueling
- GT-R Wheel Speed Missing (38B ROMS)
- GT-R TCM Tuning Guide
- GT-R RaceROM V9 Map Switching
- GT-R RaceROM V9 Rolling Launch
- GT-R RaceROM V9 Secondary Injection
General
Launch Control Method of Operation
When the Engine and Gearbox oils are up to temperature, the vehicle is stationary and the correct settings are applied to the 4WD and VDC switches along with Manual Gear Selection (not in Auto) then the factory Launch Control can be used (assuming the factory TCM ROM has it enabled by Nissan, see NOTE below!).
With your left foot on the brake and quickly pressing the Accel pedal to the floor, the engine RPM will rise very quickly to around 3300rpm or 4500rpm (depending on the exact LC version installed), this RPM will be held for around 5 seconds until the ECU will force release of the LC mode to prevent strain and heat on the clutches and gearbox.
If the 4WD switch is simply moved out of RACE mode and the test repeated then LC mode will not enable and the difference is clearly felt.
LC2 and some LC3 ROMs have the factory LC mode disabled in the TCM ROM, this can be enabled using ProECU.
Launch Control Versions Defined
LC1 (early “JF” series TCM ROMs)
Early 2008-2009 GTR models have a built in Factory Launch Control system called LC1 which is an aggressive Launch Control Mode that put considerable strain on the drivetrain.
Launch RPM is factory set at 4500rpm and is found in the Engine ECU ROM in the 1D Launch Control RPM map:
LC1 Launch Control mode will only activate when:
Oil temp is over 65 Deg C
Transmission set in Race Mode (Red Light ON)
VDC is OFF so traction control does not operate (Yellow Light ON)
Gear Level selection is in MANUAL and 1st Gear is selected
LC2 ("JF" Series TCM Roms)
On later JF cars Nissan simply disabled the launch control in the TCM ROM, this was sometimes applied during servicing at Nissan dealerships and it’s claimed that the launch control functionality was removed to maintain manufactures warranty.
You can see below the LC2 TCM ROM called JF09DBA has the factory Launch Control disabled by Nissan, to re-enable simply check the box, save the ROM and program into the TCM ECU. This will enable the LC1 Launch Control code again in the LC2 ROM
LC1 and LC2 can only be used with VDC OFF and in Manual – R mode and conditions must be met as described above.
LC3 ("JW" Series TCM Roms)
2010-2011 Gen 1 GTR models have a revised Factory Launch Control system which is enabled on all JW models. LC3 is a less aggressive Launch Control strategy that is easier on the transmission and drivetrain. LC3 works with VDC ON (Traction Control working).
Launch RPM is factory set at 3300rpm and is found in the Engine ECM ROM in the 1D Launch Control RPM map.
Launch Control mode will only activate when:
Oil temp is over 65 Deg C
VDC is ON so traction control is working (RED Light ON)
Gear Level selection is in MANUAL and 1st Gear is selected
As seen below LC3 can be enabled in Manual with or without the Transmission in R mode (Race)
If you wish to allow LC to work in other conditions (like Auto or without VDC etc) then simply enable the condition in the TCM ROM (though the associated risks must be accepted).
LC should be enabled in BOTH Mode A and Mode B if used with any Gen 1 GTR models.
LC4 and LC5 ("KB", “KJ”, “38”, “62”, “80” and “89” series TCM ROMs)
2011 Gen 2 GTR models have more refined gearbox control code, along with more advanced Launch Control strategy with improved clutch control, faster gear selection and much smoother gear changes compared to earlier TCM code versions.
LC4-5 Launch RPM is factory set at 4100rpm and is found in the Engine ECM ROM in the 1D Launch Control RPM map.
LC4-5 Launch Control mode will only activate when:
Oil temp is over 65 Deg C
VDC is ON so traction control is working (RED Light ON)
Gear Level selection is in MANUAL and 1st Gear is selected
LC4 can be enabled in Manual with or without the Transmission in R mode (Race).
If you wish to allow LC to work in other conditions (like Auto or without VDC etc) then simply enable the condition in the TCM ROM (though the associated risks must be accepted).
: LC should be enabled in BOTH Mode A and Mode B if used with any Gen 1 GTR models.
Map List
JF Series TCM (LC1)
Mode | VDC On | VDC Off |
|---|---|---|
Auto | No | No |
Auto-R | No | No |
Manual | No | No |
Manu-R | No | Yes |
JW Series TCM (LC3)
Mode | VDC On | VDC Off |
|---|---|---|
Auto | No | No |
Auto-R | No | No |
Manual | Yes | No |
Manu-R | Yes | No |
KB, KJ, 38 Series TCM (LC4 - 5)
Mode | VDC On | VDC Off |
|---|---|---|
Auto | No | No |
Auto-R | Yes | No |
Manual | No | No |
Manu-R | Yes | No |
EcuTek ProECU Nissan GTR TCM software allows the tuner to modify the LC setting conditions so that launch control can be activated without R-mode, or with VDC off or however you want.