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How to launch an AT?
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03-23-2012, 02:17 PM | #1 |
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How to launch an AT?
Hey guys,
Just curious as I am hitting up the 1/4 mile soon for the first time. My buddy just got a 2012 C63 Coupe Performance Pack and he wants to run me on the strip. I understand you have to brake-boost in 2nd gear up to 2000rpm. My question is, do you use the kickdown feature or not? I find the car feels faster when I use the kickdown off a roll. For example being in 4th gear and using the kickdown usually puts me in either 2-3 and the rpms jump real fast. However, when I just floor it (before the kickdown) in 3rd, it doesn't have that instant "jump" effect, as it's more of a buildup. Please advise, Thanks |
03-23-2012, 02:31 PM | #2 | |
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03-23-2012, 02:39 PM | #3 |
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Kickdown in that situation would be a bad thing. I'm guessing you can't get traction in first gear at all if you don't have an LSD and decent tires. Yes brake boosting in second gear is a good idea but even at 2,000 RPM you may spin...as it all depends on the track prep. If it's real sticky, you may be ok.
And let us know what you do and how it works out. We're all hoping you can take the C63
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03-23-2012, 02:40 PM | #4 |
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Nice mods you have.. yeah you can put it in 2nd and brake boost to about 2-2500 and ease in to it and shift your self or just put in DS and brake boost the same.. as stated above modulate the throttle a bit on launch then get your foot in it.. report back and let us know how you do!
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03-23-2012, 02:59 PM | #5 |
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with your set-up. Brake torque 2nd (2k-3k)build a little boost. press the peddle all the way down WITHOUT pressing kickdown button. Wait until around 40-50 stomp gas, pressing the kickdown button. (it will keep in second gear and switch to third by it self.) But you can pick your shift point, people say around 6200 rpm, but some just let it run to redline
trick is not to downshift to first. If your going less then 30-35 its going to shift down to first from a 2nd gear launch. Or if your tires are stickier enough, 1st gear brakeboost, floor it with kickdown. |
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03-23-2012, 03:31 PM | #6 |
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If you brake boost in second and try to use the kick-down right away you'll have a really slow launch. The car will downshift to 1st.. Brake boost to about 2k and then keep the pedal right before the kick-down.. Good luck on the run!
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03-23-2012, 03:38 PM | #7 |
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Thanks for your help guys!
I will report back with the results and hopefully some video footage He literally just picked up the ride a few weeks ago and he mentioned it comes stock with LSD. My tires are Hankook V12 Evo (from what ive heard they arent the greatest from a dig) |
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03-23-2012, 03:42 PM | #8 | |
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03-23-2012, 03:43 PM | #9 |
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03-23-2012, 04:08 PM | #10 |
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FYI - the kickdown won't happen when you're over 4800 RPM. Its not based on the speed you're driving but the RPMs you're at (test it on the highway).
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03-23-2012, 04:12 PM | #11 |
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I've accidentally hit the kick down at the track short shifting the 3-4 at 6200 RPM and ruined runs before.
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03-23-2012, 04:13 PM | #12 |
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If he has a p31 he will likely outtrap you a little bit. Lucky you can launch in 2nd though.... He can't so he may spin badly.
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03-23-2012, 04:18 PM | #13 |
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Brakeboost 2500-3000 rpm m2
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03-23-2012, 05:09 PM | #14 |
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NT05's hook pretty well. They are one of the closest things you can get that are like a drag radial, but still classified as a street tire.
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03-23-2012, 05:16 PM | #15 |
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How are you guys brake boosting in 2nd up to 2500 and not spinning? I need to modulate the throttle off idle in 2nd gear to get any decent traction. I am using RFT's though, so that may be the culprit even though they are practically new.
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03-23-2012, 05:26 PM | #16 |
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RFT suck! I had issues with them even on stock map! and they were practically new. They just can't take the beating. I love my nitto's!
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