Accelorometer?
Pro
Joined: Aug 2004
Posts: 575
Likes: 0
From: Richmond Hill Ontario
Have you had your car to the track? If so, you can use the data from your time slip to calculate acceleration. Acceleration can be calculated using this formula:
a = Vf - Vo/t
where a = rate of acceleration
Vf = final speed
Vo = initial speed
t = time
Example: From your timeslip, you have the following data.
Vf = 106.00mph (final speed)
Vo = 0.00mph (initial speed)
t = 13.5 seconds
a = (106.00 - 0.00)/13.5
a = 7.85mph/sec
Note: this is an average acceleration over the 1/4mile distance. You can also use this formla to calculate the average acceleration over the 1/8 mile as all the data you need is on the timeslip. You can also do your testing on the street using a stop watch by accelerating from a steady state speed, say 40mph to 60mph, in fourth gear. This can be repeated using different starting and ending speeds. If you don't want to through this exercise then the G-tech is a pretty good measuring device.
a = Vf - Vo/t
where a = rate of acceleration
Vf = final speed
Vo = initial speed
t = time
Example: From your timeslip, you have the following data.
Vf = 106.00mph (final speed)
Vo = 0.00mph (initial speed)
t = 13.5 seconds
a = (106.00 - 0.00)/13.5
a = 7.85mph/sec
Note: this is an average acceleration over the 1/4mile distance. You can also use this formla to calculate the average acceleration over the 1/8 mile as all the data you need is on the timeslip. You can also do your testing on the street using a stop watch by accelerating from a steady state speed, say 40mph to 60mph, in fourth gear. This can be repeated using different starting and ending speeds. If you don't want to through this exercise then the G-tech is a pretty good measuring device.
Melting Slicks
Joined: Sep 2003
Posts: 3,031
Likes: 74
From: If you don't weigh in you don't wrestle Road America
I have some friends that split the cost of a G-Tech RR model and once calibrated it worked great. Was accurate within 2 rwhp, but it was used at a road race track not a drag strip so I'm not sure about the 1/4 mile accuracy.
Race Director
Joined: Dec 2003
Posts: 12,599
Likes: 1
From: Texas
Originally Posted by Dyno Dan
The GTech seems to work well - IF it is calibrated properly and USED properly 
I didn't calibrate my G-timer correctly for HP measurement (weight) but the other measurements (ET, trap speed) seem to be darn close. At least its a good measurement of improvement - on my first ever run with it I went 13.3 @ 110 and my latest run (about 20 total) was 12.55 @ 114.0
Racer
Joined: Apr 2004
Posts: 387
Likes: 0
From: Rollin' Worldwide from OH10 Ohio
Originally Posted by AZBrewer
Is it hard to calibate the G-Tech? My original idea was to use this instead of going to the track.
