Hi All:

Earlier, I attached a table to post #191 and later discovered a problem with it--my car was faster to all distances, but grogan545's car was faster to all speeds except the 1/4 terminal velocity. Given these, observations, the table didn't make sense. We decided that the problem is that the NHRA correction factors apply only to 1/4 mile data.

Subsequently, I started using a regression approach to estimate interesting weather and altitude adjusted values other than 1/4 mile values. My regression equations appear to be very well fitting. Thus, I think the regression approach is a reasonable one for producing weather and altitude adjusted values for data other than 1/4 mile data.

I have attached a table that compares my best weather/altitude adjusted test results with my best unadjusted test results to start thinking about whether the regression approach produces reasonable looking results. The attachment says "so far so good." Next, I am going to compare the adjusted data from the two tests yielding my two best sets of adjusted 1/4 mile results.

 

Here is the table referred to above. As mentioned, it compare the adjusted data from the two tests yielding my two best sets of adjusted 1/4 mile results. Again, the results look good, but what ultimately is needed is a comparison of adjusted data from my car having used my regressions and adjusted data from another car having used regressions specific to it.

The right-side of the table is headed "Unadjusted," but both sets of raw data have been adjusted for weather and altitude. I forgot to change the heading for the right side.

 

Hi Friends:

I did two passes today, while the raw data were very good (but not great), my adjusted for weather and altitude data were quite good--in fact, now my two best (i.e., since I discovered a calculational error in what was my second best pass).

1/4 Speed.....105.778....105.144
1/8 Speed.......83.340......83.054
1/4 ET.............13.382.....13.444
0-100..............11.844.....12.011
0-90.................9.759.......9.878
1/8 ET..............8.684.......8.727
0-80.................8.048.......8.143
0-70.................6.475.......6.554
0-60.................4.898.......4.961
0-50.................3.772.......3.815
0-40.................2.719.......2.758
0-30.................1.678.......1.697
0-20.................0.901.......0.926
0-10.................0.277.......0.290

1/4 ET............13.382.....13.444
1,000'.............11.234....11.287
1/8 ET..............8.684......8.727
330'.................5.661......5.692
60'...................1.977......1.994

What is interesting to me is that the weather is warming up, but nevertheless I am getting relatively better adjusted times and speeds. This observation really shouldn't surprise me because comparability is the purpose of making the adjustments. But, is my car still learning? Will it continue to learn forever? I hope so. What I am saying can be seen generally by looking at my density altitude values and the related temperatures.

Date: .....................2/18......2/19....2/21...2/22......2/24....2/25....2/26......5/2
Density Altitude:...1223.2...1,239....881...913.3...1,469. 1...726..1,451...1,885.7
Temperature............49.........50......44.1.... .45........52.5......53.5....54.5....57.9

And, note, of course, that density altitute depends on things besides temperature--atmoshperic pressure, dew point, and actual altitude.

 

g-man:

I starting wondering how well my regression equations might work on you data. As an experiement, if interested, how about giving me your data for your best unadjusted run in the following format? I already have your weather and altitude adjusted data for the 1/4--so you don't need to give me those data.

1/4 Mile Speed
1/8 Mile Speed
1/4 Mile Time
0-100
0-90
1/8 Mile Time
0-80
0-70
0-60
0-50
0-40
0-30
0-20
0-10

1/4 Mile Time
1,000 Feet
1/8 Mile Time
330 Feet
60 Feet

 

Your car is learning at a steady pace.I wonder if it is adjusting to removing the mods or adjusting to 20.01?
Below is the raw data on my best run.
1/4 speed....105.5
1/8 speed.... 83.1
1/4 time...... 13.26
0-100.......... 11.35
0-90............ 9.50
1/8 time...... 8.60
0-80............... 7.85
0-70.............. 6.32
0-60.............. 4.80
0-50.............. 3.65
0-40............. 2.68
0-30............. 1.58
0-20............. .90
0-10............. .27

1/4 time....... 13.26
1000'........... 11.13
1/8.............. 8.60
330'............. 5.60
60'............... 1.92
I reviewed some of my old data from may of 05.I didn't log the weather conditions at the time but temps were above 55 F and dew points that time of the year are close to actual temps,usually about 5 less than actual temps. I had 5.00 & 5.03 0-60 times along with 13.45 & 13.47 1/4 times(grogans formula).I doubt there would be a negative altitude equivilent at that time.I now believe that what I gained in power in cold weather is offset by my loss of traction.When the weather gets better here I believe I will revert to my previous starting methods to take advantage of the better traction.

 

Update on my Gtech Meter. Should have shipped today. Tesla was waiting for a new meters to come in was the reputed delay.

 

WOW 0 to 60 in under 5?? thats too fast!

 

Thanks for providing the data. They must be for a new run because I have not yet reflected them in on the straight-line thread. It looks like a really great unadjusted pass. What was its date? I will be glad to see what happens when things warm up for you. I think that your assessment is correct. Today on my second run, which now is my second best, I intentionally brake torqued to the point where I knew that I would lose traction. I think I lost the perfect amount of traction, but my no-loss first run still was better. But, on the other hand, my first run always is the best even though I dirve around at the speed limit for a while between runs.

On second thought, are you saying the 1/4 data above are from 5/05 and the formula and that you think there would be no density altitude adustment? I need raw data where the 1/4 data were meter measured and a density altitude adjustment was needed to effectively assess whether my regressions will work somewhat OK for your car. Your data from 2/25/06 would work. Also are the data you gave above pre 20.01.00. I am trying to keep us on the post 20.01.00 page and am trying to stay away from the use of the formula in producing data that we would claim to be factual. I hope I am making sense to you. And, is this approach OK with you? Right now your adjusted data won't look so good, but, as it warms up, things should straighten out. And, we could just wait until you start getting warmer weather data.

 

Truely true. And, we both are getting them one way or the other with regularity.

 

Good deal cd. I like Tesla. They are sending me a new cord. And, when we returned home today, the phone was ringing. It was Tesla wanting my credit card number because they had been unable to give me credit for my returned Pro SS. The support guy is named Sonny, and he is very helpful--although at first it is a little hard to get through his exterior.