I quizzed about 10 of my friends who drag race and asked what is a perfect reaction time, 9/10 responded .500 seconds. There is some confusion about this. Most track nowadays list a perfect reaction time as .000 We race at englishtown and etown is one of the track that list a perfect reaction time of .000

Any track that has changed their bulbs from incandescent to LEDs will reflect the new perfect reaction time of .000





The article below explains it.

NHRA implemented two significant changes on the starting line for national events. First, the numerical value of a driver's reaction time will be modified. The modification simplifies the process of understanding a driver's reaction time to activation of the green lights on the Christmas Tree. Previously, a perfect reaction time for all Professional and some Sportsman drivers was .400-second. For the remaining Sportsman competitors, a .500-second light was considered perfect Now, the timing system will be modified to display a perfect reaction time as .000 for all categories. This change applies only to NHRA's 23 national events.

On the traditional Pro Christmas Tree, a .399 light or quicker is considered an early start, activating the red light, which results in disqualification. Under the new system, a 399 will be displayed as -.001, a .398 as -.002, and so on. Anything from a perfect reaction time of .000 and above will be a legal start The new timing system in no way affects any driver, vehicle setup, or other significant aspect of competition on the dragstrip.

Also, as previously reported, NHRA will implement the use of LED amber lights on the Christmas Tree starting system, replacing the traditional yet damage-prone incandescent lights.

"The biggest advantage is that the vibration, especially that caused by the Top Fuel and Funny Car classes, won't cause the LED bulbs to burn out like it will an incandescent," said NHRA Senior Vice President-Racing Operations Graham Light. "Amber bulb failures, especially during full Tree countdowns in the Sportsman classes, lead to reruns and other problems. We are trying to avoid that problem as well as step up our technology.

"We tested the new bulbs without problem during preseason testing in Tucson," added Light. "Racers who attend the Winternationals and subsequent events are advised that the LED lights illuminate quicker, by about three-hundredths of a second, than the incandescent lights."

Anthony

 

Going from memory so I may not be 100% but I remember reading some where the .500 is the amount of time for the body to relate an optical stimuli (seeing the light) till the time the message can cross all then nerves, to the brain, and then the brain sends a reaction signal (the launch). I’ve noticed what you said how E-town, has it based from .000, is that just calibrated with .500 as the base line? so your reading is what it is above the .5sec

b/c wouldn’t .000 be humanly impossible? Or is it getting to see how close we can estimate the green dropping?

 

It is still the same thing but they are just presenting it differently. On a pro tree (all 3 ambers flashing at the same time) a .400 would be a perfect reaction time. What that means is from the time that the ambers are triggered to the time that the green is triggered is .400 of a second. All they are doing is making it easier for the spectators to understand. If you were running on a pro tree and you got a reaction time of .430 that would equal a +.030 reaction time. In other words you were .030 seconds late from achieving a perfect light. You are still leaving .400 seconds after the ambers are lit. Same thing goes with the .500 tree but you have 3 amber lights that flash .500 of a second in succession then .500 seconds after the last amber is lit the green light is lit.

Allen

 

I was under the impression that you had to learn to react differently depending on the track you went to since the LEDs react faster. Is that the case?

I got that from reading this line...

""We tested the new bulbs without problem during preseason testing in Tucson," added Light. "Racers who attend the Winternationals and subsequent events are advised that the LED lights illuminate quicker, by about three-hundredths of a second, than the incandescent lights."

Anthony

 

Yes that is definitely true, the LED lights are much faster. I was getting consistent .508-.515 lights before the local track switched to LED lights, then all the sudden my reaction times went to the .530-.540 range. It sounds kinda funny but on a incandescent light if you pay very close attention you can actually watch the bulb start to light very dimly at first and then get brighter. With the LED lights though they come on instantly with no warning. After about three races i got use to it and was back to cutting good lights.

Allen

 

Damn, cutting .08 - .15 from a perfect light on a pro tree? That sounds almost impossible. I haven't had anyone beat me off the line and I usually get a .038 - .079 with a protree.

 

.508-.515 is not a pro tree. I have never run a pro tree before.

 

That could be a pro tree! There are lots of different kinds of protrees....The .5 tree is just the older style (pre led style). They also could have a .5 reaction time on bracket racing as well.

 

There is only one kind of Pro tree and one Amateur tree. The Pro tree lights all 3 ambers together with .400 seconds between the ambers and the green. An Amateur tree has 3 amber lights that light up in order, from top to bottom, with .500 seconds between the time the last amber goes out and the green lights.

As stated before the reaction time can be presented one of two ways on the time slip. Either with .000 being perfect, or .500 or .400 being perfect, depending on whether it was an amateur or pro tree.

Andrew