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Subject Traction and lots of practice (more info)
     
Posted by SeedyROM on May 14, 2005 at 3:45 PM
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In Reply To How do you get a 1.52 60'? (n/m) posted by EricTTZ on May 14, 2005 at 09:49 AM
     
Message I'd almost venture to say that it's equally as hard to gauge it and get it just right with the automatic as it is with the 5-speed when it comes to the initial launch, but on the 5-speed it's everything after dropping the clutch that is hard. Nailing that 1-2 shift is key as it comes in quick when the hood is lifting up from a hard launch. And then you have to hit 2-3 mid-track and that can be tough too as you're hauling ass.

I've had a few 1.5s and I've helped Dean with his launches so I can speak more directly about the automatic. Realistically, have to have a higher stall speed converter to get anything below a 1.7. Even a 1.8 can be hard on a stock converter (but it has been done in rare instances). On a non-nitrous car, the routine involves a small-medium burnout in the box as you don't want to get the tires too hot or get your rear brakes too hot from the power braking. And you'll need them on the line in a few moments. A second or two after both start smoking is usually enough on drag radials (and you WILL need those).

After the burnout, you get yourself on the line and as soon as you're staged, you hold the foot brake down as hard as you can and pull the e-brake back as far as you can. It's at that point you'll modulate the revs to about 2,000-2,500 rpm in preparation for the yellows to start. You're just holding it there for a second or two while the other guy stages. If you're trying to cut a good light, you'll usually start at the first yellow and floor it (pushing it from the modulated ~2,500rpm you were sitting at all the way to WOT). At that point you'll start to make boost as your RPMs hit the stall limit (~3,500-4,000 is the range most of us use). It will make anywhere from 6-10psi depending on your stall while sitting still. If you time it right, the car will just start to break loose or roll forward as the final yellow switches to green, you'll drop the e-brake and release the foot brake as quick as possible and you're off. I usually tape my e-brake button down so I can just let it go and it will fall back down to the bottom instead of getting stuck. All of this depends upon how good your brakes/ebrake are. If you have street pads and/or a worn e-brake you might roll out before you can even launch properly. If everything is working right and you aren't using nitrous, you should be able to "lay into it" at WOT without the car going anywhere or breaking loose. At least for a second or two while you're waiting for the green.

It takes a lot of timing and finding the sweet spot of your car. It's really not that easy to start with but once you get the hang of it you can repeat it with good results. The really hard part comes with the addition of nitrous (as in Dean and Greg's cases). Since most switches for the nitrous are based on the WOT switch, this can make launching difficult as you'll likely overpower the tires/brakes. So there are two ways you can do a nitrous launch and which way you choose is based mainly off of your brakes/ebrake/tire combination. In most cases, people will have to time it perfectly when to hit WOT (which will be a bit later than without the nitrous) because as soon as they engage that switch, the car will want to take off. So rather than "laying into it" and holding the brakes, you're really just feathering it to ~3,000 or so and then nailing it as the second yellow hits. By the time the yellow is done and is turning into green, the nitrous should take hold and have you flying down the strip as you drop the e-brake and release the foot break.

However, the ideal way to do it is to still be able to lay into it with the nitrous. Both Greg and Dean have been able to actually hold the nitrous on the line briefly before the launch (meaning they go WOT before the second yellow, hold it with the brakes and release right at the green). This is ideal as you can build boost properly and you can really feel the car wanting to go, like an angry bull waiting to break out of a pen. But again, this is tough because unless you have the right setup (tires/brakes/etc) you will likely spin the tires on the line because of how much torque/power that nitrous feeds to the drivetrain even sitting still.

As for getting a 1.6 or less on a 5-speed, that takes even more skill man. Watching Zo's videos will help people with that =)

Hope that helps somewhat. Drop me an email if you have any questions or anything.

If you think defending quality shops and site sponsors with proven records makes him a whore, then you are the ones with the problem. Stop being bitches. - October 21, 2003 at 06:16 PM

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