1/4 mile times, how to interpret?

[kunar]

anybody have any useful info about interpreting 1/4 mile times, trap speeds, 60' times, etc etc? i ran my car today and had a 16.35 @ 84.8, my 2nd run i ran a 16.40 @ 86.3, 3rd run was a 16.35 @ 87.3 and my best run was a 16.10 @ 87.3, now my question is how can my 1st and 3rd runs be identical et's but my trap speed be so different? im sure this says something about my launch or wheel spin, but what? i dont have 60' times for any of those except my last run which was a 2.47, 1/8th was a 10.42

my second question, a buddy of mine ran a nearly identical car and his best time was a 15.87 @ 82.3, how was his 1/4 better than mine but his trap speed was so low compared to mine?

 

[naford]

I will try. Your time is from when the light turns green until you hit the first trap light. Your speed should be the speed going between the first trap and the second trap. Your reaction time is why the total time is the same but your speed is diferent. Didn't the strip give you a detailed printout of your runs?

 

[feellnfroggy]

Im sure the printout is where he got all that info. It doesnt tell you what mistakes your makingthough. your 60 ft times tell you how your launching, your trap speed tells you what your top ending at. based on your times and your buddies, his car is tuned a hair better and he's driving better. Your shift times are a little too soon, when you hit the trap lights what gear are you in? it also helps to know what car your driving and whats done to it, what kinda tires? buddies tires? etc. Theres alot we need to know to interpret those times.

But all times can be improved by improving driving technique.

Your first run had better 60' times than your 3rd run that is why the time is the same but lower trap speed in the first run. it also shows you shifted too soon into one of your gears. Just work on your driving and bring results from 3 or 4 different days of racing youll see imrovement as well as be able to better analyze everything.

 

[zx6rrdan]

The timeslip with all the numbers will be able to tell you how you had a faster trap and a slower time. If you have all the partial times you'll be able to see what parts of the track you gained and lost time.

60' tells you how well you got off the line and the rest tells you how well you got down the track.

Here's a old time slip of mine when I was running my bike.

 

[kunar]

well here's the thing, all of these runs were made with a beltronics vectorpro (g-meter) now im assuming that these things are fairly accurate. we have run them at the drag strip and they seem to be extremely close to the times that are posted, but i cant guarantee complete accuracy. the second big thing was that my buddy made his runs on a dry day, i made all of my runs on a damp road. i know for a fact that i had wheel spin in first so im sure thats what brought down my 60's. reaction time isnt a variable with the g-meter either. once its calibrated and ready to run, you make your run. it starts the clock as soon as the car starts moving, there are no lights so to say. it does provide very detailed info for each run (1/4 mile, speed, 1/8 mile, 1000 feet, 330 feet, 60 feet, 0-10, 0-20, 0-30, 0-40, 0-50, etc etc) but unfortunately i didnt record any of that info for any pass except for my 4th and final run.

i guess i cant really expect much of any useful info from just the times i have, but i think its safe to assume that on the same day and same road, my car should be able to equally or out perform my buddies car? btw, mine is a 91 escort gt, his is a 94 escort gt. same engines, trans etc etc. also, 90mph is the top of 3rd gear, so i wasnt leaving 3rd till the run ended.

 

[zx6rrdan]

Sounds like the differences are grip and spinning off the line... run same day same road see how close it is. Your probably right it'll be same or close.