Ford Mustang Forums banner

1 - 20 of 26 Posts

·
Registered
Joined
·
318 Posts
Discussion Starter #1
I've never dragged at a track before, but I like watching videos of it.

I can't seem to figure out why some cars just sit at the line once the green is lit for about 1/2 a second before going.

Here's a video (not of a mustang, but the idea is the same):

http://www.youtube.com/watch?v=9IOpuGVoyCk

It's most evident at 1:30. The light goes green, and he just sits there for a long time before going. But, he still has a great time.

Is there some sort of racing where the time is measured off of when the car stars moving? I can't see him doing it accidentally, but why would you do it on purpose?
 

·
Registered
Joined
·
318 Posts
Discussion Starter #2
Hey, I just figured it out!

For those curious, your ET doesn't start until you break the beam. So, I'm assuming they just wanted to make sure they didn't redlight.
 

·
Administrator
Joined
·
53,617 Posts
WORST THREAD EVAR!!!
 

·
Administrator
Joined
·
53,617 Posts
Ok, I'm sorry. It was a question that should be answered.

FWIW, turbo cars sometimes like to "spool up" on the line and build boost. You seen GN's do it all the time.

And yes, the clocks do not start until you break the beams, hence "reaction time"

Is that better? (You know who you are Mr. PM COMPLAINT DEPARTMENT!)
 

·
Registered
Joined
·
613 Posts
Hey, I just figured it out!

For those curious, your ET doesn't start until you break the beam. So, I'm assuming they just wanted to make sure they didn't redlight.
Actually the beam is broken already by the front tire....ET starts when the beam is reattached.
 

·
Registered
Joined
·
2,465 Posts
I have sat there longer than that before. Your reaction time clock starts as soon as the green light hits, your et clock doesn't start until you break the 3rd set of lights.
 

·
Administrator
Joined
·
53,617 Posts
Actually the beam is broken already by the front tire....ET starts when the beam is reattached.

Well, you're the closest to being right here.

1. You pull into the pre-stage, the pre-stage bulb lights.
2. You pull into the second (staged) beam, the "staged" bulb lights up and now the tree is set for start. If you "deep stage" you "reattach" the beam for the pre-stage light and it goes back off, BUT THE TIMER DOES NOT START YET.

It's when you roll out of the second (STAGED) beam that the timer starts to count. There is not a "third beam" as the last two said. Many a race has been lost by rolling out of the STAGED beam before the tree comes down...
 

·
Registered
Joined
·
613 Posts
Well, you're the closest to being right here.

1. You pull into the pre-stage, the pre-stage bulb lights.
2. You pull into the second (staged) beam, the "staged" bulb lights up and now the tree is set for start. If you "deep stage" you "reattach" the beam for the pre-stage light and it goes back off, BUT THE TIMER DOES NOT START YET.

It's when you roll out of the second (STAGED) beam that the timer starts to count. There is not a "third beam" as the last two said. Many a race has been lost by rolling out of the STAGED beam before the tree comes down...
Thanks for agreeing with me.
 

·
Registered
Joined
·
617 Posts
I apologize. I thought I knew the way the timing worked, but after reading Greg's reply I looked into it, and 1trkpny is correct.
 

·
Registered
Joined
·
46 Posts
The average person's reaction time is 3/4 of a second , this is not including the time it takes for the car to react . It takes practice to consistently have a good reaction time .That is why some guys when trying new setups , won't cut a real good lite they are more concerned with the way the set up works than how quick the reaction time is.
 

·
Registered
Joined
·
35 Posts
There is not a "third beam" as the last two said. Many a race has been lost by rolling out of the STAGED beam before the tree comes down...
I think there are three beams at the starting line. If you watch nhra drag racing you will hear them talk all the time about the cars that roll in deep will lose some et because they have less of a rolling start before they trip the beam to start the timer. There is a third beam about a foot past the stage beams that may actually start the timer. Maybe not all tracks use the same timing system as the tracks that hold national events. But I have several pictures of cars on the starting line that shows the timing box with 3 holes in it. If not what is the third beam for at some tracks?
 

·
Registered
Joined
·
152 Posts
Lifted directly from the NHRA site.

"Two light beams cross the starting-line area and connect to trackside photocells, which are wired to the Christmas Tree and electronic timers in the control tower. When the front tires of a vehicle break the first light beam, called the prestage beam, the pre-stage light on the Christmas Tree indicates that the racer is approximately seven inches from the starting line.

When the racer rolls forward into the stage beam, the front tires are positioned exactly on the starting line and the stage bulb is lit on the Tree, which indicates that the vehicle is ready to race. When both vehicles are fully staged, the starter will activate the Tree, and each driver will focus on the three large amber lights on his or her side of the Tree.

Depending on the type of racing, all three large amber lights will flash simultaneously, followed four-tenths of a second later by the green light (called a Pro Tree), or the three bulbs will flash consecutively five-tenths of a second apart, followed five-tenths later by the green light (called a Sportsman, or full, Tree).

Two Separate performances are monitored for each run: elapsed time and speed. Upon leaving the staging beams, each vehicle activates an elapsed-time clock, which is stopped when that vehicle reaches the finish line."

There are only 2 beams.
 

·
Registered
Joined
·
617 Posts
But I have several pictures of cars on the starting line that shows the timing box with 3 holes in it. If not what is the third beam for at some tracks?
All the local 1/8 tracks have the 3rd hole in the box. Thats what I was basing my opinion on, but everything I've read says there are only two used for the timing system.

:shrug: I would love to know what the 3rd hole is for.
 

·
Registered
Joined
·
35 Posts
The third beam is called the "Guard Beam" I just found this online

"Some tracks also use a third infrared beam. Called a guard beam, its job is to prevent a racer from gaining an unfair advantage from a part hanging under or in front of the car (like an oil pan or spoiler) blocking both the guard and stage beams. That could give a racer a rolling start before the elasped time (ET) clock starts, reducing his ET. If the guard beam is activated while the stage beam is still on, the red foul light is triggered, disqualifying the offending racer."
 
1 - 20 of 26 Posts
Top