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Old Sep 21, 2008 | 08:43 PM
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Default Reaction time

Ok, I have a couple very simple questions. First, exactly how is reaction time measured? Also, what relevance/importance does reaction time have to the 1/4 mile? Thanks in advance
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Old Sep 21, 2008 | 09:05 PM
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Ok, I apologize for asking such questions before researching elsewhere. Found the answer:

"The reaction time announced is the time that the vehicle took to move off of the starting line compared to when the last amber bulb lit up. A reaction time of .543 means the vehicle left the line exactly .043 seconds after the green came on (.500 after the last amber plus .043 = .543). And a reaction time of .410 means the vehicle left .080 seconds before the green bulb lit which activated the red light instead…a foul start. A perfect reaction time is .500 seconds. A reaction time over .6 seconds is considered marginal and over .7 is slow."
- http://www.toyotaspeedwayatirwindale...ite/howto.html
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Old Sep 22, 2008 | 08:31 AM
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Yep and reaction is purely from seat time and experience in the car. As you get more line experience the reaction comes down. However the reaction has NO impact on the 1/4mi if you're not running anyone...where it comes into play is if you run someone and they kill you on the tree or you kill thier reaction which can make or break a close race.
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Old Sep 23, 2008 | 11:44 AM
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A little info on reaction time:

Most tracks now measure a perfect light as .000 instead of the .500 you mentioned. And if your running brackets or heads-up, a .100 (.600 in the old format) is late and getting sleepier! Most competitive guys are going .040 or better.

Reaction time has no effect on 1/4 mile time because the et clock doesn't start until the car rolls out of the stage beam. You can run 13.50s with a .015 light or 13.50s with a 2.050 light.

Derek
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Old Sep 24, 2008 | 03:18 AM
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This is all true, but watch where you stage in the lights because that does affect your ET by shortening the distance of your roll out!
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Old Sep 24, 2008 | 04:34 AM
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Originally Posted by 358chevycamaro
This is all true, but watch where you stage in the lights because that does affect your ET by shortening the distance of your roll out!
Very important to remember. I am a consistent .040 R/T driver. Anything above that and I am puzzled.

When I first started I would usually get around .050s which is pretty good, but every once and a while I would have a R/T which was like .150. It completely boggled my mind because I felt I was launching the same.

I found out that I was staging inconsistently, now I can pull off .030s usually every time up there without having to worry at all. The best advice is to just stage as shallow as possible, to where the stage light is almost blinking on and off. Then from there learn how and when to react on the last amber.

Next season is going to be an experience, as I am getting a 3600 stall converter put in, and I have a feeling it is going to screw with my R/Ts.
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Old Sep 24, 2008 | 04:45 AM
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In my index class we run a .500 protree and if you get worse than .30 expect to lose
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Old Sep 24, 2008 | 07:28 AM
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Reaction only matters when your racing in a class, and/or event, OR if its a grudge match. Otherwise, practice your launching technique, especially in a M6 car.
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Old Sep 24, 2008 | 10:12 AM
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Originally Posted by Villain281H
A little info on reaction time:

Most tracks now measure a perfect light as .000 instead of the .500 you mentioned. And if your running brackets or heads-up, a .100 (.600 in the old format) is late and getting sleepier! Most competitive guys are going .040 or better.

Reaction time has no effect on 1/4 mile time because the et clock doesn't start until the car rolls out of the stage beam. You can run 13.50s with a .015 light or 13.50s with a 2.050 light.

Derek
To add to Derek's info ...

To find out if the track uses the .000 light or the .x00 light format, see if they are using LED light or the old incandescent lights. The LED come on faster and (from what I last recall) NHRA suggested using the LED with a .000 light, and incandescent with the old format.
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