Launch Control:
What is it?
On the Nissan R35 GT-R, the car has a computer controlled dual clutch and transmission. The computer control allows for the car to drive semi-smoothly from idle by just the right amount of slip to engagement. Launch control will hold the car to a certain RPM to allow a quicker off the line start, and faster 0-60 times.
How do you engage it?
Originally it took the mode selector switches in R-R-OFF to activate launch control. Eventually in LC3,4,and 5 launch control could be activated with VDC ON.
What is LC1?
LC1 was the first version of launch control. It was a violent clutch drop, wheel spin, and wheel hopping, 1st gear death. Undocumented officially, with the setup switches in R-R-OFF, the car would allow for a 4500 rpm automated clutch drop. Done a few times is no big deal, however when done 26 times in a row, owners managed to kill GR6 gearboxes. Specifically they sheared the teeth off first gear. After a bit of an uproar, the launch control was changed to what we call LC2. LC2 allowed for 3000 rpm launches and was much less violent than the LC1 launches. LC2 was retro fitted to most 2009 GT-R's, standard on the 2010 cars.
What is LC2?
- Launch Control remains, but the maximum allowable engine speed with the VDC system switched off will be reduced from the current 4,500 rpm to between 3,000 and 3,500 rpm. The clutch engagement program will also change to reduce driveline stress, e.g., less abrupt engagement on launch.
- When launching with the VDC on, the new programming will allow for higher engine speeds and a more aggressive clutch engagement than the current setup.
- Nissan reiterated that launching the GT-R with the VDC off is not covered by the warranty.
What is LC3?
For 2011 launch control was again revised, and would allow for a 3300 rpm launch with R-R-R, making the launch covered under warranty.. However, if the car got a lot of wheelspin, the car would bog and loose power, basically falling on its face.
What is LC4?
First used on the 2012 Nissan GT-R. In 2012(US), the launch control was again revised. This time it is an actual advertised feature, called R Mode Start, with limits. LC4 allows for four launches prior to it requiring a mile and a half drive to cool the transmission down. The quick numbers are generated with the setup switches in R- Comf - R. 4000 rpms comes up, and 0-60 times happen in anywhere from 2.8- 3.2 seconds. Check out this video of a drag race between a 2011 GT-R with LC3 and a 2012 Nissan GT-R with LC4. Videos like this, plus 0-60 times in the 2's made the early Nissan GT-R owners lust after LC4.
What is LC5?
Used on the 2013 Nissan GT-R. For 2013, there may be a further improvement in the launch control. Nissan says that 0-60 mph has dropped to the 2.7 second range. From Nissan's own charts, it looks like there is not as much of a dip in RPM after launch. User impressions say that the car holds gears a little longer in auto mode, but no huge differences between LC4 and LC5.
Cobb Tuning has been working tirelessly on the upgrades. Just recently they got the LC4 version of the Nissan launch control to work on the 2009-2010 Nissan GT-R. Along with getting the LC4 version to work, Cobb has also downloaded and ported the LC5 software over as a alpha for the Accessport with TCM control - 006. Its great to see Cobb Tuning keeping the Nissan GT-R community updated with all the latest tweaks to get all they can get out of their cars.
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