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2003-2009 Nissan 350Z

Best way to launch

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Old May 10, 2005 | 08:56 PM
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kangol99
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Default Best way to launch

I was wondering how you Automatic tranny guys launch your 350z to race someone or at the track.
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Old May 10, 2005 | 09:04 PM
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uhh floor it?
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Old May 10, 2005 | 10:22 PM
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Originally Posted by kangol99
I was wondering how you Automatic tranny guys launch your 350z to race someone or at the track.
Look in rear view mirror for cop. Step on the brake hard with your left foot and hold the throttle to a pre-determined RPM with your right foot thus pre loading the engine, transmission, drive shaft, diff and axle shaft. Look left for dumb driver running red light. Look ahead for blind pedestrian about to cross street with brain dead seeing eye dog. Look ahead for dummy about to turn in from driveway straight ahead. Release left foot and press right foot to floor. Back off if tires start to lose a bit o traction. Lift foot off throttle precisely at 5mph over speed limit. Brake hard

First step is recommended. My bad. 1/4 mile in 12 seconds Honda 750K motorbike, hard left and right sweeper. Talked to cop. Gave me ticket for 5 over! Said I looked real good through the sweepers. True story.
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Old May 10, 2005 | 10:24 PM
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.......... sweet
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Old May 10, 2005 | 10:29 PM
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Originally Posted by kangol99
I was wondering how you Automatic tranny guys launch your 350z to race someone or at the track.
Brake-torque launch. Use the brakes to preload the tranny and FI if you got it then release the brake and floor the throttle at the same time.

... 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. Proper brake-torquing will have a catapult effect, immediate torque multiplication gradually traded for velocity until it couples or the next shift occurs.

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 May 10, 2005 | 10:55 PM
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Brake Torque launching vs. flooring in manual mode vs. flooring it in D?

Is there that big of a difference? Maybe .1-.3 difference?
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Old May 11, 2005 | 07:41 AM
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Originally Posted by Edison_Chen
Brake Torque launching vs. flooring in manual mode vs. flooring it in D?

Is there that big of a difference? Maybe .1-.3 difference?
You can do a brake-torque launch in either manual mode or auto mode. The problem with manual mode is you now introduce driver error but on the other hand you might get lucky enough to pick better shift points than the computer. It won't be consistent.
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