Really dumb question!!

[snow0925]

Could someone please explain to me the logic of this:
If one car does the quarter mile in 13.4 at 103mph than why does it take another car... lets say going 105mph, 13.6 to reach the end of the quarter mile?? Wouldn't the one going faster finish the quarter mile quicker?? What's more important the time or the speed...I suppose it's the time, but than why include the mph in the equation. Many Thanks

 

[RalleyRed]

I'm hopeing that there are no dumb questions just dumb answers!

That being said I'm going to shutup now and wait for someone that knows the answer to your question so I can learn this time too.

Rick

 

[Rick Daniel]

If the faster car to longer to get off of the line than the slower car then the slower car could still have a better time. Its all about launching off of line.

 

[Tephy]

Hi

I dont know for sure that I am correct in this but.....

if one car takes 5 secs to get to 103 mph and the other takes 7 secs to reach 105 mph then the 1st car will travel for 2 secs at 103 mph while the other one is still accelerating to 105 mph and hence will cover the distance quicker.

hope this makes sense

Tephy

 

[HOTMOTORSPORTS]

Some of it is in the reaction time. How much time it takes for you to step on the gas and release the clutch etc. Your speed may not be effected, but just standing there for just part of a second after the time has started will make the difference. You'll reach the same speed in the end. Remember that when the green lite goes on, the clock begins. An important part of the time slip to look at is the 0 to 60 feet time. That will tell you if you were slow at the start.

This is why there are more automatic transmissions being used. Their start time (reaction time) is much quicker and consistent. It all comes down to this: consistency with quick reaction times wins races!

I hope I said what I meant!

Chuck

 

[DRTH VTR]

drag racing

I run a stock '97 coupe at the strip. I have no trouble running faster than 100MPH (at 14.1seconds @ 2600 ft elevation). There are other cars that run a faster e.t. than I do, but cannot crack that 100MPH barrier. There are two things to think about:
1. The other cars get up to speed faster (lower gears, stickier tires), but don't have as much top end horsepower. I catch up as we go down the track. I get there later, but am catching them, and am going faster.
2. There is a misconception about e.t. The staging lights are about a foot behind the start line. The time starts when you cross the start line. The e.t. is the time from when you break the start line until you cross the finish line. The reaction time has NOTHING to do with e.t. If car A has an e.t. of 12.5 seconds and a reaction time of 0.8 and car B has an e.t. of 12.6 seconds and a reaction time of 0.6 seconds, car A has a faster e.t., but lost the drag race by 0.1 seconds. You see this on TV all the time. It is possible to get the green light and just sit there for quite a while and still not have started the elapsed time sequence.
Make sense?

 

[Edmond]

Could someone please explain to me the logic of this:
If one car does the quarter mile in 13.4 at 103mph than why does it take another car... lets say going 105mph, 13.6 to reach the end of the quarter mile?? Wouldn't the one going faster finish the quarter mile quicker?? What's more important the time or the speed...I suppose it's the time, but than why include the mph in the equation. Many Thanks

Especially in your case since you do have the 6 speed, the driver skill becomes a much bigger part of the equation.

I know that they print quarter mile times, but I think they're (GM) somewhat cautious about quarter mile speeds.

Isn't a higher trap speed the number that most drag racers covet more than a time? I'm not sure about that one.

 

[Tomrw]

Not a dumb question. Let me try to explain how I see it.

The velocity of 103 or 105 MPH is the speed at which the car is traveling at the end of the quarter mile. Time is how long it took, so simply the car with the 13.4 had a faster average speed over the 1/4 mile distance than the 13.6 car. I would think that the MPH is what counts.
Tom

 

[HOTMOTORSPORTS]

To DRTH VTR,

According to your #2 Statement and scenario, reaction time had EVERYTHING to do with winning. When two people are so close as are pro-street, dragsters, etc. Reaction time is all they have! Watch the next time your at a race (or watching TV) and the cars are exacty matched, you'll notice it.

When the light goes green, "staying at the light" or "sitting at the light" is a slang for ssllooww reaction times. I'm sure you hit the gas pedal just before the light goes green to get a better start time (reaction time). I've lost my share of races because of poor reaction times (as much as I hate to admit it).

Chuck

 

[DRTH VTR]

drag racing

I do a little drag racing in my '97 automatic, so I speak from my own learning and experience at the track.
One person above said that the time starts when the light turns green. That is not correct. The time starts when you cross the start line. If a racer gets a good reaction time (0.500 is ideal on a "sportsman" tree), but runs a slower time than the second racer, he can still win if the other racer has a slow reaction time.
The "sportsman" tree is the one where the yellow lights go on one at a time, every 0.5 seconds, then the green light goes on. The "pro" light is where all the yellow lights go off all at once and the green lights up 0.4 seconds later. This is the one that is usually seen on TV.

Bracket racing is a different animal altogether. The purpose for this type of race is so that slower cars can race faster cars. Each car leaves at a different time, as explained below. Each driver predicts his e.t. based on trial runs. This is called "dialing in". The predicted time is the "dial in time". If a person has a dial of 14.1 and another person has a dial of 14.6, the slower car leaves 0.5 seconds sooner. You are disqualified if you go quicker than your dial in (this is called "breaking out"). The winner is generally the person who gets closer to their dial-in without going faster. It is more complicated than that, as reaction time is variable. I think of it as the first one who gets to the finish line without going faster than the dial-in, wins. The trick in bracket racing is to be consistent, so the dial-in is very close, and to get a good reaction time.

I think that the e.t. is what drag racing is all about. The trap speed is interesting, but it is who gets to the finish line first that matters. This is the combination of elapsed time and reaction time.

I hope this makes sense. As you can tell, I like to race. I was the 2002 VetteFest drag racing champion. VetteFest is one of the premier corvette events in the Northwest!

 

[DRTH VTR]

drag racing

HOTMOTORSPORTS:

You say "According to your #2 Statement and scenario, reaction time had EVERYTHING to do with winning."

Chuck- What I meant to say is that reaction time has nothing to do with e.t. If you watch the races, you will see that a racer can run a faster e.t. than his opponent and still lose. If reaction time was part of the e.t., this could not happen. The e.t. is the time between breaking the start light and breaking the end light. Sitting at the light for ten seconds will not affect the e.t., but it sure will affect who wins the race!

I think we both mean the same thing here.
Jim "DRTH VTR"

 

[HOTMOTORSPORTS]

Again, as you just stated above, reaction time is everything and explains most of the reason for the original question.

Chuck

 

[Corvette Concepts]

...and the answer is....!!!

The MPH on a drag strip run are calculated over the last 60 feet of the track.......you could have a car that ran slow at the launch and really crank at the end and it will have a higher trap speed....reaction time has nothing to do with the MPH...reaction time actually doesn't even have anything to do with the elapsed time....the elapsed time is started when you launch the car and it breaks the beam....reaction time will come into play when two cars have the same ET....the best reaction time would be the winner......a perfect reaction time is .500.......not many of those out there!!! Our Pewter 99 Fixed Roof Coupe runs the quarter in 11.80 seconds at 117.83 MPH in Florida.....I'd like to drag this car up to a cooler climate and try it out. This is a stock block car with our 425SS package on it....naturally aspirated...no nitrous.....

 

[HOTMOTORSPORTS]

I think I know what's going on here. I've never thought of reaction time as a piece. To me reaction time is an intricate part of the end ET. I also believe that MPH can be relative with reaction time even for a 10th of a MPH depending on if you hog the first or second trip light.

Example very much like DRTH VTR:

Car A runs 8.65 with a .45 reaction

Car B runs 8.62 with a .42 reaction

Both cars claim they can run 8.70. All other things being equal, Car B won due to better reaction time.


Another: Car A and B run 8.90

Car A claims 8.95 but had .45 reaction
Car B claims 8.90 and had .50 reaction

In this case they did have the same ET, but it was effected by the reaction time.

I can't be all wrong on this. I've been involved in these scenarios.

Looking back on replies, it looks like we disagree, but I think we are describing as we see it, but the same result.

This site is fun!

Chuck Mailhot
Also Have '76 Nova w/468 Big Block Blower 1,120 HP with Methanol. (Looking for C3 Corvette Chassis for it). Too scary for street, removed Methanol, now 720 HP on pump gas (2% underdrive), inspected and registered.

 

[DRTH VTR]

e.t.

This is a fun site!
What I am talking about is the time ticket that I get handed at the end of a race.
The elapsed time is the time from when I broke the light at the start line until I broke the light at the end line. The reaction time is not a piece of the e.t. printed on that ticket. I am splitting hairs here, but I think that it is a common misconception that the e.t. is from when the light turns green until the car crosses the finish line. It is not. Theoretically, I could sit at the start line for 30 seconds after the green light, then hit it and run an e.t. of 14 seconds. I would lose the drag race, but I had a quick e.t.!
At the bottom of the ticket at the strip that I go to, there is something called "margin of victory", which compares the two cars and includes the reaction time, elapsed time, etc.
Whee!

 

[HOTMOTORSPORTS]

You're stuck on the statement I made at first, but I corrected it by saying the slang for slow reaction was sitting at the light, standing at the light, staying at the light. I know the time doesn't start until you trip the lights.

Chuck