How to Figure reaction time in Drag Racing

[TomoHawk]

I gave a go at drag racing one night last summer for fun. IIRC, my "reaction time" was 0.7 seconds, and a guy I met there said that's not good for serious competition, and I should work on it.

AFAIK, the reaction time includes in your reaction to hit the gas pedal, and the time it takes for the engine to get the RPMs up to get the torque converter to spin and get the drive wheels turning.

So if the reaction time was 0.7s and the green light illuminates 0.4s after the amber ones, then you should theoretically hit the gas before the amber light illuminates?

There must be something I'm missing from my Internet research on drag racing. Can anyone help or explain? Any tips? I'm not going after trophies, but it's not so good seeing the other car out in front by the time you thing you have the gas pedal pushed to the floor.

It's a stock JATCO 3 spd. with no line lock or other fancy stuff.

thxZ

[Stanley]

3 weeks ago at S.I.R. in Tucson was my first legal race, so I'm no expert. To me it's all about testing the car (subtract reaction time), going fast and having fun. Also, there's a community. My first run reaction was worse than yours, the second was near perfect (beginners luck) and the last one I red-lighted. I've got a 240 with JATCO 3-speed too. Brakes on, stomp on the gas when the 2nd staging light comes on, let off the brakes when the third yellow light comes on. Shift at exactly the right time, whenever that is. There's some practice trees on the internet. There's some in-depth articles about reaction time, but they're mainly for pro racers. See you out there.

[TomoHawk]

The Interne practice trees are fine to see how your mouse buttons are working, but I don't see any correlation to real experience. When you are there, you have adrenalin, some fear, no experience, a bunch of "flashing lights," a LOT of noise, some strange, random thoughts, and et cetera. You can use the practice trees to figure out your game plan, but then you have to take it with you to the strip, or the street, to practice and learn it so well that all the noise and stuff at the race track can be factored out. I think knowing how your vehicle responds to your control changes is the biggest part of working out your timing.

I suppose somewhere there is a mobile application that uses GPS data to measure your actual reaction time, so you can practice without having to drive 50+ miles to a track.

Edited June 4, 2012 by TomoHawk

[Bonzi Lon]

The 'reaction time' is the amount time it takes from when the light turns green to when your front wheels break the beam. Where you place your wheel between the beams makes a difference, there will be a small amount of space from pre-stage to staged, then a shorter distance if you knock out the top light. It all comes down to practice, practice, practice in the real experience.

Bonzi Lon

[Diseazd]

Anticipation......You have to time the amber lights....intuitively so you actually nail it before the green light. It takes practice watching the lights to anticipate the green. You may get disqualified occasionally, but that's what drag racing is all about.......cutting seconds off the clock.

[TomoHawk]

Diseazed got it. The RT is not really from when the lights turns green to when your front wheels break the beam. but the time the from the last amber to when the wheel breaks the beam. Alls and w perfect reaction time is 0.400 seconds, not 0.0 seconds. If you got an RT of 0.0, then you got a red-light. So if I got a .700, it took 0.300 seconds to hit the gas and get rolling. That sounds kinda good, actually (0.3 seconds) for ran old car with an old automatic with a 600 RPM stall.

Actually, the tire probably broke the beam as soon as you let of the brake, and it still takes 1+ seconds to get the car going or accelerating. If you could two-foot it, you could probably actually get an RT of 0.400 with the car accelerating, not just rolling.

My trans doesn't seem to like the power-braking stuff.

Edited June 4, 2012 by TomoHawk

[Arne]

I can't imagine getting consistent and good RTs w/o power braking.

[TomoHawk]

I suppose you could screw the idle up to about 3000, or use a solenoid-operated high-idle valve? That ought to be fun in the staging lanes.

[TomoHawk]

BTW- reaction times are 0.400 or 0.500 seconds, depending on which starting system you use.

[TomoHawk]

The thing here is how to figure out when you need to jump on the gas pedal to get the perfect .400 or .500 second RT. It takes so long for you to react to the light, to jump on the gas, for the engine to start spinning, the torque converter to build pressure, and finally for the car to start moving through the starting lights.

So far it seems that trial-and-error is the way. But instead of wasting your money and a day (or several) to try things, there should be a way to figure out about how much anticipation you need to have. Unless someone has any ideas, it looks like you need some electronic stuff to figure this thing out.