The Nissan GT-R has had a poorly kept secret of launch control since it was released in 2007 in Japan. The first launch control was called LC1. Undocumented officially, with the setup switches in R-R-OFF, the car would allow for a 4500 rpm automated clutch drop. This violent clutch drop at high RPM caused a lot of wheel hop. Done a few times is no big deal, however when done 26 times in a row, owners managed to kill 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.
For 2011 launch control was again revised, and would allow for a 3300 rpm launch with R-R-R. However, if the car got a lot of wheelspin, the car would bog and loose power, basically falling on its face. This has caused some issues for guys with 2011 cars trying to drag race. John Shepherd, the GT-R transmission builder of choice for the quickest GT-R's in the world has a 2011 Nissan GT-R. He has gone as quick as 9.92 with the car, but he felt there was still more in it. Tym Switzer from Switzer Performance stopped by Sheptrans and helped him out with his transmission reprogramming it to LC1. Check out the video below.
Source: NAGTROC
For 2011 launch control was again revised, and would allow for a 3300 rpm launch with R-R-R. However, if the car got a lot of wheelspin, the car would bog and loose power, basically falling on its face. This has caused some issues for guys with 2011 cars trying to drag race. John Shepherd, the GT-R transmission builder of choice for the quickest GT-R's in the world has a 2011 Nissan GT-R. He has gone as quick as 9.92 with the car, but he felt there was still more in it. Tym Switzer from Switzer Performance stopped by Sheptrans and helped him out with his transmission reprogramming it to LC1. Check out the video below.
We reprogrammed both the ECM and TCM in the car and we've got everything working together properly so it looks like we're good to go. John is currently running the ProEFI on his car so in the video you will hear a 2 step limiter being used to control the rpm to a lower level than the typical LC1 4000+ rpm limit which is not needed for his combination. Besides... due to the fact that John spends so much time processing all of the transmission builds we, AMS and so many other shops send in... he's still running a stock gearset in his car. I'm hoping he gets that changed out soon.
Source: NAGTROC
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