The Official G-Meter Testing Thread
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Originally Posted by Znod' post='244969' date='Feb 23 2006, 05:32 PM
Here is some data for you to start thinking about.
Unadjusted
1/4 Mile Speed 102.710 103.620 102.910 102.830 102.710 103.020 103.240 102.270 102.860 102.780 Average--102.895
Variance--0.126472222
1/4 Mile Time 13.629 13.744 13.702 13.742 13.720 13.764 13.686 13.742 13.759 13.774
Average--13.726
Variance--0.001921511
Adjusted
1/4 Mile Speed 104.083 105.005 104.285 104.213 103.683 103.996 104.218 103.274 103.870 103.789 Average--104.042
Variance--0.206969822
1/4 Mile Time 13.451 13.565 13.523 13.562 13.593 13.637 13.559 13.61 13.627 13.642 Average--13.577
Variance--0.003461656
It would be nice to know what the adjusted data are more variable. As you were thinking, they should be less variable--ideally showing zero variability. I'm going to start reading some of the SMOKEmUP tech articles if I can find time. So much to do so little time.
Unadjusted
1/4 Mile Speed 102.710 103.620 102.910 102.830 102.710 103.020 103.240 102.270 102.860 102.780 Average--102.895
Variance--0.126472222
1/4 Mile Time 13.629 13.744 13.702 13.742 13.720 13.764 13.686 13.742 13.759 13.774
Average--13.726
Variance--0.001921511
Adjusted
1/4 Mile Speed 104.083 105.005 104.285 104.213 103.683 103.996 104.218 103.274 103.870 103.789 Average--104.042
Variance--0.206969822
1/4 Mile Time 13.451 13.565 13.523 13.562 13.593 13.637 13.559 13.61 13.627 13.642 Average--13.577
Variance--0.003461656
It would be nice to know what the adjusted data are more variable. As you were thinking, they should be less variable--ideally showing zero variability. I'm going to start reading some of the SMOKEmUP tech articles if I can find time. So much to do so little time.
#212
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I've deleted some posts in this thread.
Please, don't attack one another, and if something doesn't interest you, ignore it. Let other people talk about the things that interest them.
Thanks.
Please, don't attack one another, and if something doesn't interest you, ignore it. Let other people talk about the things that interest them.
Thanks.
#213
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Originally Posted by das' post='245030' date='Feb 23 2006, 06:26 PM
I've deleted some posts in this thread.
Please, don't attack one another, and if something doesn't interest you, ignore it. Let other people talk about the things that interest them.
Thanks.
Please, don't attack one another, and if something doesn't interest you, ignore it. Let other people talk about the things that interest them.
Thanks.
#214
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Originally Posted by grogan545' post='244994' date='Feb 23 2006, 05:54 PM
I have read several more articles on weather corrections for drag racing.I really have to reread and try to digest what they are saying.As you have said before at the moment they are"over my bow".Some racers actually take their weather station to the starting line with them.They are not satisfied with the stationary weather equipment at the site.
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Originally Posted by Znod' post='245036' date='Feb 23 2006, 06:30 PM
Cool. I'd like to know what you find out. I think I'll get a weather station.
I will be out of town next week so no further testing until I get back.But I do intend to test over various conditions to see if the corrected numbers are at least reasonably close.
I also did some "donkey math"(math without basis in fact)on estimating corrected 0-60 Time.If you take the diff between your raw & corrected 1/4 mile et's and either add or subtract(depending on the direction of the correction)this diff to your 0-60 time it comes out pretty close.I did this on every run that I had data on and it was within .03 sec with only 2 exceptions which were about .1 sec.I did by comparing my uncorrected times times to ea other and used this method to check the 0-60 time against my known times.I hope I didn't confuse you.Example:
14.109 raw et,0-60 time 5.65 sec(my drag strip times)
13.45 corrected et
.659 diff
5.65-.659=4.99 sec corrected 0-60 time
Looking at one of my 5.00 times I estimated 1/4 time of 13.45
Diff of only .01 between actual 0-60 and estmated 0-60
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Originally Posted by grogan545' post='245155' date='Feb 23 2006, 10:20 PM
I also did some "donkey math"(math without basis in fact)on estimating corrected 0-60 Time.If you take the diff between your raw & corrected 1/4 mile et's and either add or subtract(depending on the direction of the correction)this diff to your 0-60 time it comes out pretty close.I did this on every run that I had data on and it was within .03 sec with only 2 exceptions which were about .1 sec.I did by comparing my uncorrected times times to ea other and used this method to check the 0-60 time against my known times.I hope I didn't confuse you.Example:
14.109 raw et,0-60 time 5.65 sec(my drag strip times)
13.45 corrected et
.659 diff
5.65-.659=4.99 sec corrected 0-60 time
Looking at one of my 5.00 times I estimated 1/4 time of 13.45
Diff of only .01 between actual 0-60 and estmated 0-60
14.109 raw et,0-60 time 5.65 sec(my drag strip times)
13.45 corrected et
.659 diff
5.65-.659=4.99 sec corrected 0-60 time
Looking at one of my 5.00 times I estimated 1/4 time of 13.45
Diff of only .01 between actual 0-60 and estmated 0-60
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Originally Posted by Znod' post='245202' date='Feb 24 2006, 12:21 AM
Try to stay in touch while gone. I see what you mean about donkey math. I have been thinking about decent ways to get corrected zero to 60's also. No real progress yet. Did your slip show zero to 60, or was this reading from your meter? Regardless, I don't see why the diff in 1/4 raw versus corrected would equal diff in zero to 60 raw versus corrected. But, I'll see if I can justify what you are saying. Maybe I don't understand what you are saying.
The 0-60 time on my drag strip run was from the GT2.The strip doesn't measure 0-60.I found no scientific justification for the 1/4/0-60 correlation,It just seems to correlate better than any other method that I tried.The factors derived from the weather corrections don't come close.Maybe I don't understand what I'm saying either.I used this method on all of my runs that I could and tried it on some of your runs also.It is not perfect but more times than not it is less than .05 sec diff.I am sure there is a math solution to this but to date I have not discovered it.
I will try to stay in touch next week.I will be traveling for work with a friend who has a lap top(I don't).I am sure I can find time in the evenings to keep up with the latest.
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Originally Posted by grogan545' post='245464' date='Feb 24 2006, 01:12 PM
I will try to stay in touch next week.I will be traveling for work with a friend who has a lap top(I don't).I am sure I can find time in the evenings to keep up with the latest.
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I am back from travel, but no meter yet. I got mine back in their hands Monday last so I do not expect my replacement until sometime next week. I wanted a chance to get down some good baseline before I get into CIP 20.xx which looks now like March 10/11 time frame.
I'll be sure to gather Wx data as well, although I believe all my runs will be at sea level or below (during hurricane season).
I'll be sure to gather Wx data as well, although I believe all my runs will be at sea level or below (during hurricane season).
#220
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Originally Posted by cobradav' post='245491' date='Feb 24 2006, 02:34 PM
I am back from travel, but no meter yet. I got mine back in their hands Monday last so I do not expect my replacement until sometime next week. I wanted a chance to get down some good baseline before I get into CIP 20.xx which looks now like March 10/11 time frame.
I'll be sure to gather Wx data as well, although I believe all my runs will be at sea level or below (during hurricane season).
I'll be sure to gather Wx data as well, although I believe all my runs will be at sea level or below (during hurricane season).
I just ask questions about all of what you said on another thread.