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Discussion Starter · #1 ·
Okay, I tried this for the first time today. I got 3.8s on my only successful attempt. All other attempts were aborted by the computer due to brake slippage, despite having the brake lever on the stop......

What am I doing wrong?
 

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Okay, I tried this for the first time today. I got 3.8s on my only successful attempt. All other attempts were aborted by the computer due to brake slippage, despite having the brake lever on the stop......

What am I doing wrong?
What RPM are you launching at with full break pressure?

I am 3.2 to 3.3 all day smashing gas a stop and launch.....
 

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Discussion Starter · #3 ·
I started with 3000rpm but quickly dropped it to 2400.

Am i correct in applying brake pressure with left foot and full throttle with my right foot? Isn’t launch control supposed to limit the rpm to what i selected? It doesn’t seem to.
 

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Have you tried it without launch control? Just a little power braking to about 1800 to 2000 rpm in track mode. I was able to get 3.3 on my first try and 3.1 on my second just doing that. I still get a little wheel spin so I may try dropping the RPM's a little more on my next few try's. As I've said before, I fully expect to drop below 3 when I get it perfect.

I only used launch control a couple of times in my previous SRT's and to be honest, it just never seemed to work like I was expecting it to. So I just used power braking and I got as good (or better) numbers than most I've seen posted. So I'm expecting the same for the TH.
 

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Discussion Starter · #5 ·
Tried it without launch mode today. 3.6 so getting better. Brakes on, 2000RPM then brakes off whilst simultaneously flooring it.
I want to see 3.2 or less.
 

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Have you tried it without launch control? Just a little power braking to about 1800 to 2000 rpm in track mode. I was able to get 3.3 on my first try and 3.1 on my second just doing that. I still get a little wheel spin so I may try dropping the RPM's a little more on my next few try's. As I've said before, I fully expect to drop below 3 when I get it perfect..
3.2 doing the same thing. First time was 3.4. Second was 3.2. No Launch Mode.
 

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A couple items I learned regarding LAUNCH CONTROL....

with vehicle in sport/track/custom mode, push as hard as you can on brake pedal. push LC and you will see brake pressure on dashboard and pedal goes to the floor. when around 1300 psi, STAB the gas pedal! If you roll into the gas, LC will disengage. there is no timers on LC, so for practice you do not have to be in a rush, including when it's doing it's dat-dat-dat-dat mode. if you do the above and you don't get the dat-dat-dat two step mode, then you rolled into the gas instead of stabbing it.

I hope this helps =)
 

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Discussion Starter · #8 ·
OK, since I'm obviously a little dense, are you saying that the brake pedal goes to the floor after pushing LC?
I've never tried drag racing so obviously my technique is awful. I assume you stab the gas pedal whilst simultaneously releasing the brake at that point?
 

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1. Set launch control RPM to 1800 in the app

2. Track mode on the dial

3. Press the Launch button

4. Steering wheel straight, level ground, brake pushed to the floor as hard as you can.

5. Push the accelerator to the floor, while the brake is still to the floor.

6. Let off the brake quickly.

7. Instant 3.1-3.4 60', depending on tire setup and surface.
 

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What eeldreth said is correct - Only difference is you do not have any time limits meaning for practice there is no rush. There are no timers on the launch control system.

EXAMPLE: you can hold the brake pedal down and you do not have to immediately STAB the gas..... and once the gas is STABBED, you can hold it there for as long as you want doing it's "dat-dat-dat-dat" until you release the brake. <---- this does build up heat in engine and converter. Start out at 1000 rpm until you get use to how the launch control works, then you can step it up higher for actual launches. Releasing the gas pedal will cancel launch control also. You can practice all day long in your driveway bringing it up to set launch rpm, goes into "dat-dat-dat" mode, then release the gas, and launch control is aborted.

On mine, you have to try to put the brake pedal through the floor (1300 psi on dash) AND then the gas pedal has to be STABBED!
 

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You will know it when you get there =)

The engine goes into firing half the cylinders when IN launch mode.... hence the "dat-dat-dat" mode. It has a very unique sound and will be apparent when you get there. High horsepower racers call their system a two step, essentially putting their vehicle into "dat-dat-dat" mode holding it at their set rpm launch mode. When the brake is released, engine goes back to firing all cylinders.

WHEN YOU HEAR IT, IT WILL MAKE SENSE.
 

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Is there any magic as to the PSI number for the brake when doing a launch? thx
 

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Discussion Starter · #14 ·
Thanks for that description..

I'll post here when I get a decent result!!

On a different note I drove 105 miles home last night. It was raining, dark, all highway mileage. I set the adaptive cruise at 75mph, Econ mode, turned up the premium sound, let the TH do all the work keeping me safe and in my lane and mellowed out in comfort. And got 16.9mpg!!! My 5.7L Hemi was only 2 mpg better. Who says the TH isn't 'green' when you want it to be :)
 

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GTS21 -

I know mine when in launch control (dat-dat-dat/two step/1300 psi) drove through the brakes when set at 2000 rpm. I have since burnished the brakes and it now holds.

Mine will go over 1300 psi, whereas a friends only goes to 1280.

There's a lot of vehicle to keep in place, so the more pressure (my opinion) the better the hold....... especially if you have the launch RPM set high. Knowing mine goes 1300 psi plus, I now look for that on the dash B4 I hit the gas pedal.
 

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Discussion Starter · #16 ·
3.1 :)

Used Rolly's technique. brake pedal pushed as hard as I could, saw 1300psi and put accelerator to the floor whilst releasing brakes. That's a lot of fun crammed into 3.1 seconds!!!!
 

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Good for you!

Just remember that there is NO RUSH.... you don't have to immediately release the brake when the throttle is stabbed. Actually works better if you don't. That's when you go into two step-dat/dat/dat mode, with brake and gas down just sitting. ENJOY!
 

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You guys may be right about using launch control and I think it's a interesting option to consider in a controlled environment like a drag strip. However, by just using a little power braking, my best times have been as good or better than anyone I've seen published (so far) using LC. I've only made a few serious runs but I have already seen 3.1 by just a little power braking. Is anyone going to be taking the time at a stop light to use LC or instead just use a quick power brake, if you are "in to such things" :) ? In reality, most people I've seen "competing for speed" (not me of course :D), "start" anywhere from ~30 to ~70+ mph.
 
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