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Launching a AT.

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Old Aug 2, 2005 | 06:43 PM
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Default Launching a AT.

whats the best way to launch a auto and does the traction on or off make a difference?
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Old Aug 2, 2005 | 06:47 PM
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TC sucks. Just push the gas. That's all there is to an AT. Get a manual and you'll need to practice, just don't floor it in the auto and you'll be fine.
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Old Aug 2, 2005 | 07:20 PM
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you could always work the stall converter to launch out better.
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Old Aug 2, 2005 | 08:17 PM
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don't do anything silly like reving from neutral and then popping it into drive unless you want to mess up your auto.
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Old Aug 2, 2005 | 09:12 PM
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Do a brake torque launch. If you do it properly you will multiply the torque coming from the engine and flash your RPMs closer to the engine's peak torque. If you have a turbocharger you can pre-load your turbos this way and launch under boost. I don't remember what the 5AT's stock stall speed is but you want to get the TC close to that speed just before it couples at the starting line. Once it couples or locks it will trade torque for velocity. Once you reach near redline upshift and your TC should uncouple and torque multiply again as long as you are accelerating.

If you can't brake torque, just floor the pedal in auto mode and don't let up or help the transmission to shift. Depending on how the tranny adapted to you even twitching might cause the tranny to upshift. When the tranny has adapted to you and you use it correctly you can almost just think when you want to shift and the tranny will do it for you if it's in full auto mode.

Also, don't let off on the gas during the shift like you would in an MT. Just slam the shifter into gear or let the computer do it.

Turn TCS off in most conditions.
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Old Aug 2, 2005 | 09:52 PM
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how exactly do you brake torqe? do you just keep your foot on the brake, and hit the gas, then release the brake at a certain rpm? is that bad for the brakes? id like to test drive a auto and see the difference for myself
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Old Aug 2, 2005 | 11:58 PM
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Now using my patented "Super Mind Control" technique on Misko418 >>> "Get the Z in a 6 speed....6 speeeeddd......Auto Tranny is for old ladies...Get the 6 speeeeddd"

Just kidding...LOL

Enjoy whichever one you get..or already have!!

Last edited by Racer Z; Aug 3, 2005 at 12:01 AM.
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Old Aug 3, 2005 | 08:30 AM
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Originally Posted by mikewagon
how exactly do you brake torqe? do you just keep your foot on the brake, and hit the gas, then release the brake at a certain rpm? is that bad for the brakes? id like to test drive a auto and see the difference for myself
Here's an excerpt from Modern Racer, hope it helps.

... But it may be surprising for some to know that many pro drag-racing cars have heavy-duty auto gearboxes. That's because the brake-torque launch is an automatic specialty. This launch involves keeping the car stationary by flooring the brakes with the left foot, while using the right foot to rev up the engine against the torque converter. In technical terms, this preloads the entire drivetrain with the stress of a launch, allowing the engine to rev closer to its power and torque peaks at the starting line. Brake-torquing is also beneficial for turbocharged engines as it allows boost to build up before the launch, reducing turbo lag. The only problem is that there is a lot of stress on the transmission, and the consequent heat build-up can destroy your automatic gearbox. Unless your car has too much power for the tires to handle, a brake-torque launch usually will not spin the wheels. This is because the automatic transmission absorbs the shock by design, and brake-torquing actually reduces stress on the rest of the drivetrain. Instead of a sudden massive load, the drivetrain has the torque applied slower instead of one huge jolt.

If your car has power brakes, you could apply the brake-torquing technique even better. At the starting line, shift your auto gearbox into neutral and floor the brake pedal with your left foot. Rev the engine once and quickly get off the throttle. You will feel the brake pedal sink further to the floor. This greatly increases the braking force. Now shift back into gear. You will now be able to rev up the engine even higher against the torque converter. ...
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Old Aug 3, 2005 | 02:07 PM
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so left foot on breaks, put it in manual mode into first, put it into about 5k rpms then let go of the break and then continue from there?

if thats waht im supposed to do, seems like it would be bad for the car, but i dont know jack about cars.
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Old Aug 3, 2005 | 02:23 PM
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Originally Posted by Forrest80
so left foot on breaks, put it in manual mode into first, put it into about 5k rpms then let go of the break and then continue from there?

if thats waht im supposed to do, seems like it would be bad for the car, but i dont know jack about cars.
You'll only be able to rev up to a little over 2k rpms with an automatic. Anything above that the car will start to move. It doesnt work like a manual transmission with a clutch.
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Old Aug 3, 2005 | 03:15 PM
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You can get past 2k rpm, just hold that break good :P.
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Old Aug 3, 2005 | 03:29 PM
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how do you guys launch with a 6sp tranny?
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Old Aug 3, 2005 | 03:29 PM
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Drop the clutch?
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Old Aug 3, 2005 | 06:51 PM
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Originally Posted by mikewagon
how exactly do you brake torqe? do you just keep your foot on the brake, and hit the gas, then release the brake at a certain rpm?......
keep your foot on the brake and accelerator(sp?) till you get to 2.75-3K RPM.....release the brake(add gas) and ride that torque curve like a roller coaster.....
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Old Aug 3, 2005 | 08:12 PM
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Originally Posted by Forrest80
so left foot on breaks, put it in manual mode into first, put it into about 5k rpms then let go of the break and then continue from there?

if thats waht im supposed to do, seems like it would be bad for the car, but i dont know jack about cars.
On the stock TC you wouldn't want to go to 5k because you'll be on the downside of the torque curve after 4700. On the stock TC you wouldn't be able to get to 5k without causing severe stress or damage to your drivetrain and brakes. Once, you exceed the TC's stall speed the tranny will want to couple or lock and move the car. When the TC is locked, it is the AT equivalent of a regular MT with the clutch engaged. It would be the same as having the clutch engaged and reving the engine with the brakes on. You''ll burn your TC and stress the engine, drivetrain and brakes.

I think you can safely torque to 2.75k - 3k with the stock tranny.
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Old Aug 3, 2005 | 09:04 PM
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ok so its ok to hold the break and accelerate up until about 3K? it wont hurt my car or antyhing? i always thought that it was bad for the car to do that...
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Old Aug 4, 2005 | 08:44 AM
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I done this several times.

1) turn the TCS off

2) get in manual mode.

3) Left foot on break, Right on gas

4) Rev to about 3k... if you rev a little higher, you will spin your wheels before you launch...especially if you're still on stock tires. If you push it even more, you will be doing a burnout.

5) When you're ready... Foot off the break, and mash the gas.... and you're gone!

Advice: Do not stay in step 4 for an extended amount of time. Only do it when you are ready to launch. IMO, its to much stress for the AT.


Have fun!
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Old Aug 4, 2005 | 08:50 AM
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Cool thread! Tag
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Old Aug 4, 2005 | 10:41 AM
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Try this: Go to an empty parking lot. Turn of TCS. Put into manual mode. Mash the brake with your left foot and get the rpms up to between 4-5 rpm. Let go of the brake 100% and at the same time mash the gas and cut the wheel left as hard as you can..... it's a lot of fun. This is also the way I launch minus cutting the wheel.
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Old Aug 4, 2005 | 02:24 PM
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another dumb question from me, shift up at about 5k rpms afterwords each time? or let it get near redline then shift,

noticeing my automatic when trying to accelerate fast, will go to redlines before shift.
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