The Official G-Meter Testing Thread
03-17-2006, 10:28 AM
#351
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Originally Posted by grogan545' post='256396' date='Mar 17 2006, 01:47 PM
I happen to live in a well populated area.This site would be perfect at 3 am,but impossible because of the deer.No hunting in my area therefore we are grossly overpopulated with deer.They feed constantly at night and are very unpredictable around the roadsides.
You can eliminate that run on 2-25.I forgot that I did give you the weather data.The run was not one of my best.
You can eliminate that run on 2-25.I forgot that I did give you the weather data.The run was not one of my best.
03-17-2006, 01:27 PM
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Originally Posted by cobradav' post='256417' date='Mar 17 2006, 02:28 PM
Sounds like when I lived in Bucks Co PA
03-21-2006, 10:14 AM
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Hi All
I made 2 more runs yesterday with mixed results.The first run was made with all controls"on".The second run was made with traction controls"off".I had tremendous wheelspin with traction off,the rpm's went to 6500 and shifted to second gear at about 20 mph causing the car to bog down.I decided to complete the run anyway and was somewhat surprised at some of the data.See below.
.....................run 1(controls on) run2(traction off)
1/4................ 13.39/105.50........... 13.62/105.70
1000'............. 11.27...................... 11.47
1/8................ 8.72/82.6................ 8.92/82.7
330'............... 5.70....................... 5.90
60'................. 1.95....................... 2.12
0-100............. 12.09..................... 12.07
0-60............... 5.00...................... 5.25
temp 38F
barometer 30.09
dew point 17F
altitude 400'
As shown by my data the speeds at the 1/8 & 1/4 were not affected,in fact the 105.7 is the best unadjusted speed I have ever recorded.However the et's were all off due to the wheelspin start.I expected the results to be much worse on run 2 than they actually were.I still must wait for warmer weather before testing with controls off.
Zman work your magic with the weather corrections.I am sure they will affect these numbers in a negative manner.
I made 2 more runs yesterday with mixed results.The first run was made with all controls"on".The second run was made with traction controls"off".I had tremendous wheelspin with traction off,the rpm's went to 6500 and shifted to second gear at about 20 mph causing the car to bog down.I decided to complete the run anyway and was somewhat surprised at some of the data.See below.
.....................run 1(controls on) run2(traction off)
1/4................ 13.39/105.50........... 13.62/105.70
1000'............. 11.27...................... 11.47
1/8................ 8.72/82.6................ 8.92/82.7
330'............... 5.70....................... 5.90
60'................. 1.95....................... 2.12
0-100............. 12.09..................... 12.07
0-60............... 5.00...................... 5.25
temp 38F
barometer 30.09
dew point 17F
altitude 400'
As shown by my data the speeds at the 1/8 & 1/4 were not affected,in fact the 105.7 is the best unadjusted speed I have ever recorded.However the et's were all off due to the wheelspin start.I expected the results to be much worse on run 2 than they actually were.I still must wait for warmer weather before testing with controls off.
Zman work your magic with the weather corrections.I am sure they will affect these numbers in a negative manner.
03-21-2006, 02:19 PM
#354
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Originally Posted by grogan545' post='258110' date='Mar 21 2006, 02:14 PM
Zman work your magic with the weather corrections.I am sure they will affect these numbers in a negative manner.
Your results:
Air Temp 38 (?F)
Altimeter Setting 30.09 (in)
Dew Point 17 (?F)
Altitude 400 (Feet)
Density Altitude -1064.6 (feet)
First Run to Sea Level:
Your results:
Density Altitude -1064.6.4 (feet)
Uncorrected ET 13.39 (sec)
Uncorrected MPH 105.5 (mph)
Corrected ET 13.54
Corrected MPH 104.293
First Run to 500'
Your results:
E.T. 13.54 (sec)
Trap Speed 104.293 (mph)
Measured DA 0 (feet)
Corrected to 500(feet) DA
Corrected ET 13.611 (sec)
Corrected Trap Speed 103.735 (mph)
Second Run to Sea Level:
Your results:
Density Altitude -1064.6.4 (feet)
Uncorrected ET 13.62 (sec)
Uncorrected MPH 105.7 (mph)
Corrected ET 13.772
Corrected MPH 104.49
Second Run to 500'
Your results:
E.T. 13.772 (sec)
Trap Speed 104.49 (mph)
Measured DA 0 (feet)
Corrected to 500(feet) DA
Corrected ET 13.845 (sec)
Corrected Trap Speed 103.931 (mph)
Zero to 60:
First Run: 5.221
Second Run: 5.475
03-22-2006, 05:27 PM
#355
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Originally Posted by Znod' post='258207' date='Mar 21 2006, 06:19 PM
Here you go.
Your results:
Air Temp 38 (?F)
Altimeter Setting 30.09 (in)
Dew Point 17 (?F)
Altitude 400 (Feet)
Density Altitude -1064.6 (feet)
First Run to Sea Level:
Your results:
Density Altitude -1064.6.4 (feet)
Uncorrected ET 13.39 (sec)
Uncorrected MPH 105.5 (mph)
Corrected ET 13.54
Corrected MPH 104.293
First Run to 500'
Your results:
E.T. 13.54 (sec)
Trap Speed 104.293 (mph)
Measured DA 0 (feet)
Corrected to 500(feet) DA
Corrected ET 13.611 (sec)
Corrected Trap Speed 103.735 (mph)
Second Run to Sea Level:
Your results:
Density Altitude -1064.6.4 (feet)
Uncorrected ET 13.62 (sec)
Uncorrected MPH 105.7 (mph)
Corrected ET 13.772
Corrected MPH 104.49
Second Run to 500'
Your results:
E.T. 13.772 (sec)
Trap Speed 104.49 (mph)
Measured DA 0 (feet)
Corrected to 500(feet) DA
Corrected ET 13.845 (sec)
Corrected Trap Speed 103.931 (mph)
Zero to 60:
First Run: 5.221
Second Run: 5.475
Your results:
Air Temp 38 (?F)
Altimeter Setting 30.09 (in)
Dew Point 17 (?F)
Altitude 400 (Feet)
Density Altitude -1064.6 (feet)
First Run to Sea Level:
Your results:
Density Altitude -1064.6.4 (feet)
Uncorrected ET 13.39 (sec)
Uncorrected MPH 105.5 (mph)
Corrected ET 13.54
Corrected MPH 104.293
First Run to 500'
Your results:
E.T. 13.54 (sec)
Trap Speed 104.293 (mph)
Measured DA 0 (feet)
Corrected to 500(feet) DA
Corrected ET 13.611 (sec)
Corrected Trap Speed 103.735 (mph)
Second Run to Sea Level:
Your results:
Density Altitude -1064.6.4 (feet)
Uncorrected ET 13.62 (sec)
Uncorrected MPH 105.7 (mph)
Corrected ET 13.772
Corrected MPH 104.49
Second Run to 500'
Your results:
E.T. 13.772 (sec)
Trap Speed 104.49 (mph)
Measured DA 0 (feet)
Corrected to 500(feet) DA
Corrected ET 13.845 (sec)
Corrected Trap Speed 103.931 (mph)
Zero to 60:
First Run: 5.221
Second Run: 5.475
It seems like the weather adjustments do great "damage" to your results. I decided to try to get a handle on what, if anything, might be wrong. So, I did the tablulation below for the 36 post-mods tests I have collected data on. In principle, the tabulation tells us what we would expect--what's implied by the words im bold. Thus, on the basis of the tabulation alone, I can't find fault with the weather adjustments. However, the tabulation alone does not say anything about whether the weather adjustments produce under or over adjustments.
Density Altititude Above Actual Altitude of 1,600'/Weather-Altitude Adjusted 1/4 time Better than Altitude Adjusted 1/4 Time = 12
Density Altititude Below Actual Altitude of 1,600'/Weather-Altitude Adjusted 1/4 time Worse than Altitude Adjusted 1/4 Time = 24
To try to get a handle on the issue in italics above, I found six of my passes where the average density altitude was very close to the opposite of yours given above (three with a density altitude of 1,223.2
and three with a density altitude of 943.1). My "reverse" density-altitude average is 1,083.15 ((1223.2 + 943.1)/ 2), while your density altitude from above was -1,064.6. After adjusting first to sea level and then to 500', my average 1/4 time for the six passes is 13.586 (unadjusted 13.670), while your adjusted to 500' 1/4 time for your first run above is 13.611 (unadjusted 13.39).
The difference in our adjusted values is .025--favoring the downward adjusted for my car over the upward adjustment for your car. However, the difference could arise because my car is .025 secs faster on average at 500' or because the weather corrections are biased in favor of downward adjustments as opposed to updward adjustments. Also, the difference could arise partially because my average was adjusted by 18.55 additional feet (1,083.15 - 1064.6). Finally, the difference could arise simply because of uncontrolled factors--e.g., wheel spin, auto/driver weight, etc.
At this point, my conclusion is that the weather adjustments are likely to be unbiased whichever way the adjustiment go. In other words, I doubt that they favor adjusting in one direction at the expense of the other and, thus, that we should feel comfortable in presenting weather and altitude adjusted to 500' data for comparative purposes. What do you think?
03-23-2006, 09:11 AM
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Originally Posted by Znod' post='258698' date='Mar 22 2006, 09:27 PM
Hi g-man:
It seems like the weather adjustments do great "damage" to your results. I decided to try to get a handle on what, if anything, might be wrong. So, I did the tablulation below for the 36 post-mods tests I have collected data on. In principle, the tabulation tells us what we would expect--what's implied by the words im bold. Thus, on the basis of the tabulation alone, I can't find fault with the weather adjustments. However, the tabulation alone does not say anything about whether the weather adjustments produce under or over adjustments.
Density Altititude Above Actual Altitude of 1,600'/Weather-Altitude Adjusted 1/4 time Better than Altitude Adjusted 1/4 Time = 12
Density Altititude Below Actual Altitude of 1,600'/Weather-Altitude Adjusted 1/4 time Worse than Altitude Adjusted 1/4 Time = 24
To try to get a handle on the issue in italics above, I found six of my passes where the average density altitude was very close to the opposite of yours given above (three with a density altitude of 1,223.2
and three with a density altitude of 943.1). My "reverse" density-altitude average is 1,083.15 ((1223.2 + 943.1)/ 2), while your density altitude from above was -1,064.6. After adjusting first to sea level and then to 500', my average 1/4 time for the six passes is 13.586 (unadjusted 13.670), while your adjusted to 500' 1/4 time for your first run above is 13.611 (unadjusted 13.39).
The difference in our adjusted values is .025--favoring the downward adjusted for my car over the upward adjustment for your car. However, the difference could arise because my car is .025 secs faster on average at 500' or because the weather corrections are biased in favor of downward adjustments as opposed to updward adjustments. Also, the difference could arise partially because my average was adjusted by 18.55 additional feet (1,083.15 - 1064.6). Finally, the difference could arise simply because of uncontrolled factors--e.g., wheel spin, auto/driver weight, etc.
At this point, my conclusion is that the weather adjustments are likely to be unbiased whichever way the adjustiment go. In other words, I doubt that they favor adjusting in one direction at the expense of the other and, thus, that we should feel comfortable in presenting weather and altitude adjusted to 500' data for comparative purposes. What do you think?
It seems like the weather adjustments do great "damage" to your results. I decided to try to get a handle on what, if anything, might be wrong. So, I did the tablulation below for the 36 post-mods tests I have collected data on. In principle, the tabulation tells us what we would expect--what's implied by the words im bold. Thus, on the basis of the tabulation alone, I can't find fault with the weather adjustments. However, the tabulation alone does not say anything about whether the weather adjustments produce under or over adjustments.
Density Altititude Above Actual Altitude of 1,600'/Weather-Altitude Adjusted 1/4 time Better than Altitude Adjusted 1/4 Time = 12
Density Altititude Below Actual Altitude of 1,600'/Weather-Altitude Adjusted 1/4 time Worse than Altitude Adjusted 1/4 Time = 24
To try to get a handle on the issue in italics above, I found six of my passes where the average density altitude was very close to the opposite of yours given above (three with a density altitude of 1,223.2
and three with a density altitude of 943.1). My "reverse" density-altitude average is 1,083.15 ((1223.2 + 943.1)/ 2), while your density altitude from above was -1,064.6. After adjusting first to sea level and then to 500', my average 1/4 time for the six passes is 13.586 (unadjusted 13.670), while your adjusted to 500' 1/4 time for your first run above is 13.611 (unadjusted 13.39).
The difference in our adjusted values is .025--favoring the downward adjusted for my car over the upward adjustment for your car. However, the difference could arise because my car is .025 secs faster on average at 500' or because the weather corrections are biased in favor of downward adjustments as opposed to updward adjustments. Also, the difference could arise partially because my average was adjusted by 18.55 additional feet (1,083.15 - 1064.6). Finally, the difference could arise simply because of uncontrolled factors--e.g., wheel spin, auto/driver weight, etc.
At this point, my conclusion is that the weather adjustments are likely to be unbiased whichever way the adjustiment go. In other words, I doubt that they favor adjusting in one direction at the expense of the other and, thus, that we should feel comfortable in presenting weather and altitude adjusted to 500' data for comparative purposes. What do you think?
I don't know if you ever get better than standard conditions in Phoenix because of the altitude.Is it possible to get sea level or better equivilent there?
03-23-2006, 02:38 PM
#357
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Originally Posted by grogan545' post='258936' date='Mar 23 2006, 01:11 PM
Your data looks good Zman.The .025 diff is certainly is close enough to be caused by uncontrolled factors or differences in car performance.What I am going to do is wait for weather that is very close to standard conditions(april,may) and gather data,then wait for weather conditions worse than standard(usually july,august)and gather data.All data should give consistant results when weather corrected.I think .05 sec differences would be acceptable under these circumstances.I would really like to do this at a drag strip where it is easier to control the test conditions.What do you think Zman?
I don't know if you ever get better than standard conditions in Phoenix because of the altitude.Is it possible to get sea level or better equivilent there?
I don't know if you ever get better than standard conditions in Phoenix because of the altitude.Is it possible to get sea level or better equivilent there?
Your results:
Air Temp 30.04 (?F)
Altimeter Setting 30 (in)
Dew Point 23.8 (?F)
Altitude 1600 (Feet)
Density Altitude -0 (feet)
Your results:
Air Temp 32 (?F)
Altimeter Setting 30.1 (in)
Dew Point 14.5 (?F)
Altitude 1600 (Feet)
Density Altitude 2 (feet)
The closest I have come to 0 yet is 787.9--53.5 F; 30.7 in.;19 F.
Oh, and I think your idea is a good one. I am working on an analysis that will hint at the results of your experiment--and its likely success. I'll post the analysis later tonight. We are on our way to dinner right now.
03-23-2006, 06:12 PM
#358
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Originally Posted by grogan545' post='258936' date='Mar 23 2006, 01:11 PM
Your data looks good Zman.The .025 diff is certainly is close enough to be caused by uncontrolled factors or differences in car performance.What I am going to do is wait for weather that is very close to standard conditions(april,may) and gather data,then wait for weather conditions worse than standard(usually july,august)and gather data.All data should give consistant results when weather corrected.I think .05 sec differences would be acceptable under these circumstances.I would really like to do this at a drag strip where it is easier to control the test conditions.What do you think Zman?
I don't know if you ever get better than standard conditions in Phoenix because of the altitude.Is it possible to get sea level or better equivilent there?
I don't know if you ever get better than standard conditions in Phoenix because of the altitude.Is it possible to get sea level or better equivilent there?
I am not where I thought I would be on the analysis I mentioned. I decided that I was taking the wrong approach, but I may have found something more interesting--using contrary thinking. What I have found may have implications for your idea that weather adjustments/density altitude adjustments over 4adjust, perhaps way over adjust, on cars that are able to tailor their tuning to weather conditions.
What I found is that my car's maximum torque and HP appear to be pretty much independent of density altitude. Remember that the Pro RR presents maximum torque and HP using a no-nonsense approach. That is, these values are presented without adjustment for any losses. The analysis below relates to maximum torque, but the maximum HP analysis implies the same conclusion.
I need to give the analysis, and its implications, more thought, but the analysis appears to suggest that we should not adjust for weather--i.e., should not use density altitude. In other words, it suggests that our performance values may be more accurate if adjusted only for altitude--or perhaps for altitude and only a small percentage of the "implied" density altitude correction (because my analysis may imply a small tendency for my car to produce more HP given better weather--i.e., there is something of a negative correlation between density altitude and HP). I believe, at this moment, that all of what I am saying is consistent with my best unadjusted 1/4 times occurring when the weather tends to be "better" as indicate by the underscored torque values below, but with my best weather and altitude adjusted 1/4 times occurring when the weather tends to be worse. Somehow, this scenario doesn't seem to play right in my ears.
Good thinking earlier; I never gave up on finding a way to show whether or not your idea is valid. I should have thought of this simple approach earlier. What do you think now--given what's below? (DA = Density Altitude: Tq = Torque)
..DA....Max Tq
2151.3 242.4
2151.3 242.6
2085.6 245.9 237.850 (average last 3 similar DA-Tq values)
1771.5 235.1
1765.0 245.8
1765.0 247.4
1763.5 244.2
1763.5 246.0 239.580 (average last 5 similar DA-Tq values)
1722.4 244.0
1722.4 244.9
1695.0 241.1
1695.0 245.4 238.200 (average last 4 similar DA-Tq values)
1554.4 233.3
1554.4 245.3
1516.0 241.7
1516.0 246.0
1516.0 246.7
1509.3 240.0 238.700 (average last 6 similar DA-Tq values)
1415.4 247.2
1415.4 248.7 242.300 (average last 2 similar DA-Tq values)
1239.0 244.1
1223.2 244.5
1223.2 247.1
1223.2 247.5
1102.1 235.4
1102.1 249.4 241.350 (average last 6 similar DA-Tq values)
977.80 243.8
977.80 244.2
977.80 245.0
943.10 244.1
943.10 244.2
943.10 247.1 237.100 (average last 6 similar DA-Tq values)
801.30 244.9
801.30 252.1
801.30 253.1
787.90 248.3
787.90 248.3
787.90 251.4 243.317 (average last 6 similar DA-Tq values)
Maybe our really stupendous results should be presented after all.
EDIT: I calculated the moving-average maximum torque values below to get a smoothed "picture" of the sligthly negative correlation between my car's HP and density altitude. I calculated the averages by adding the next torque value (not numbered above) to the preceeding average calculation until I got to average 19. Then, I started dropping "oldest" torque values from the successive average calculations once I got to average 20. i.e., average 19 is based on torque values 01-19 (which, as mentioned, are not numbered above); average 20 is based on torque values 02-20, average 21 is based on torque values 03-21, etc., etc. When I got to average 38, I started leaving out the 2 "oldest" torque values for the next average calculation. The result is that average 44 is based on only the final five torque values.
Moving-Average
...Maximum
.....Torque
01. 236.7
02. 237.9
03. 238.4
04. 239.0
05. 239.0
06. 239.6
07. 239.1
08. 239.1
09. 239.1
10. 239.2
11. 238.8
12, 238.8
13. 238.9
14. 238.9
15. 238.7
16. 238.9
17. 239.1
18. 238.8
19. 238.9
20. 239.3
21. 239.1
22. 239.0
23. 239.0
24. 239.1
25. 239.4
26. 239.8
27. 239.6
28. 239.5
29. 239.3
30. 239.6
31. 239.3
32. 239.3
33. 239.4
34. 239.9
35. 240.3
36. 240.2
37. 240.6
38. 240.7
39. 240.8
40. 241.1
41. 240.5
42. 240.7
43. 241.5
44. 243.0
03-24-2006, 02:18 AM
#359
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Hi All:
Briefly, I took the Z06 out for two passes this morning. I had good passes--not my best--but still good. I may not have had enough wheel spin for a best as I had quite a bit on the passes that yielded my best 0 to 60's (3.77 and 3.961 unadjusted). But, my goal remains getting the best times possible without abusing my car--i.e., no powershifting, minimal wheel spin, and no high-RPM launches. Consistently, my 60' times are slightly above 2.0 (ugh!). I need 1.9's or less for "bests." Here is what I got--adjusted for weather and to 500'.
Pass one: 12.15 @118.794 (0 - 60 4.112 unadjusted; probably 3.9 adjusted)
Pass two: 12.19 @ 118.641 (0 - 60 4.169 unadjusted; probably > 3.9 and < 4.0 adjusted)
I got to 120 pretty fast on both runs. I can't remember for sure right now, but I think my first pass yielded 12.816 before adjustment (probably 12.57 adjusted).
Briefly, I took the Z06 out for two passes this morning. I had good passes--not my best--but still good. I may not have had enough wheel spin for a best as I had quite a bit on the passes that yielded my best 0 to 60's (3.77 and 3.961 unadjusted). But, my goal remains getting the best times possible without abusing my car--i.e., no powershifting, minimal wheel spin, and no high-RPM launches. Consistently, my 60' times are slightly above 2.0 (ugh!). I need 1.9's or less for "bests." Here is what I got--adjusted for weather and to 500'.
Pass one: 12.15 @118.794 (0 - 60 4.112 unadjusted; probably 3.9 adjusted)
Pass two: 12.19 @ 118.641 (0 - 60 4.169 unadjusted; probably > 3.9 and < 4.0 adjusted)
I got to 120 pretty fast on both runs. I can't remember for sure right now, but I think my first pass yielded 12.816 before adjustment (probably 12.57 adjusted).
03-24-2006, 08:38 AM
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Originally Posted by Znod' post='259173' date='Mar 23 2006, 10:12 PM
Hi Again g-man:
I am not where I thought I would be on the analysis I mentioned. I decided that I was taking the wrong approach, but I may have found something more interesting--using contrary thinking. What I have found may have implications for your idea that weather adjustments/density altitude adjustments over 4adjust, perhaps way over adjust, on cars that are able to tailor their tuning to weather conditions.
What I found is that my car's maximum torque and HP appear to be pretty much independent of density altitude. Remember that the Pro RR presents maximum torque and HP using a no-nonsense approach. That is, these values are presented without adjustment for any losses. The analysis below relates to maximum torque, but the maximum HP analysis implies the same conclusion.
I need to give the analysis, and its implications, more thought, but the analysis appears to suggest that we should not adjust for weather--i.e., should not use density altitude. In other words, it suggests that our performance values may be more accurate if adjusted only for altitude--or perhaps for altitude and only a small percentage of the "implied" density altitude correction (because my analysis may imply a small tendency for my car to produce more HP given better weather--i.e., there is something of a negative correlation between density altitude and HP). I believe, at this moment, that all of what I am saying is consistent with my best unadjusted 1/4 times occurring when the weather tends to be "better" as indicate by the underscored torque values below, but with my best weather and altitude adjusted 1/4 times occurring when the weather tends to be worse. Somehow, this scenario doesn't seem to play right in my ears.
Good thinking earlier; I never gave up on finding a way to show whether or not your idea is valid. I should have thought of this simple approach earlier. What do you think now--given what's below? (DA = Density Altitude: Tq = Torque)
..DA....Max Tq
2151.3 242.4
2151.3 242.6
2085.6 245.9 237.850 (average last 3 similar DA-Tq values)
1771.5 235.1
1765.0 245.8
1765.0 247.4
1763.5 244.2
1763.5 246.0 239.580 (average last 5 similar DA-Tq values)
1722.4 244.0
1722.4 244.9
1695.0 241.1
1695.0 245.4 238.200 (average last 4 similar DA-Tq values)
1554.4 233.3
1554.4 245.3
1516.0 241.7
1516.0 246.0
1516.0 246.7
1509.3 240.0 238.700 (average last 6 similar DA-Tq values)
1415.4 247.2
1415.4 248.7 242.300 (average last 2 similar DA-Tq values)
1239.0 244.1
1223.2 244.5
1223.2 247.1
1223.2 247.5
1102.1 235.4
1102.1 249.4 241.350 (average last 6 similar DA-Tq values)
977.80 243.8
977.80 244.2
977.80 245.0
943.10 244.1
943.10 244.2
943.10 247.1 237.100 (average last 6 similar DA-Tq values)
801.30 244.9
801.30 252.1
801.30 253.1
787.90 248.3
787.90 248.3
787.90 251.4 243.317 (average last 6 similar DA-Tq values)
Maybe our really stupendous results should be presented after all.
EDIT: I calculated the moving-average maximum torque values below to get a smoothed "picture" of the sligthly negative correlation between my car's HP and density altitude. I calculated the averages by adding the next torque value (not numbered above) to the preceeding average calculation until I got to average 19. Then, I started dropping "oldest" torque values from the successive average calculations once I got to average 20. i.e., average 19 is based on torque values 01-19 (which, as mentioned, are not numbered above); average 20 is based on torque values 02-20, average 21 is based on torque values 03-21, etc., etc. When I got to average 38, I started leaving out the 2 "oldest" torque values for the next average calculation. The result is that average 44 is based on only the final five torque values.
Moving-Average
...Maximum
.....Torque
01. 236.7
02. 237.9
03. 238.4
04. 239.0
05. 239.0
06. 239.6
07. 239.1
08. 239.1
09. 239.1
10. 239.2
11. 238.8
12, 238.8
13. 238.9
14. 238.9
15. 238.7
16. 238.9
17. 239.1
18. 238.8
19. 238.9
20. 239.3
21. 239.1
22. 239.0
23. 239.0
24. 239.1
25. 239.4
26. 239.8
27. 239.6
28. 239.5
29. 239.3
30. 239.6
31. 239.3
32. 239.3
33. 239.4
34. 239.9
35. 240.3
36. 240.2
37. 240.6
38. 240.7
39. 240.8
40. 241.1
41. 240.5
42. 240.7
43. 241.5
44. 243.0
I am not where I thought I would be on the analysis I mentioned. I decided that I was taking the wrong approach, but I may have found something more interesting--using contrary thinking. What I have found may have implications for your idea that weather adjustments/density altitude adjustments over 4adjust, perhaps way over adjust, on cars that are able to tailor their tuning to weather conditions.
What I found is that my car's maximum torque and HP appear to be pretty much independent of density altitude. Remember that the Pro RR presents maximum torque and HP using a no-nonsense approach. That is, these values are presented without adjustment for any losses. The analysis below relates to maximum torque, but the maximum HP analysis implies the same conclusion.
I need to give the analysis, and its implications, more thought, but the analysis appears to suggest that we should not adjust for weather--i.e., should not use density altitude. In other words, it suggests that our performance values may be more accurate if adjusted only for altitude--or perhaps for altitude and only a small percentage of the "implied" density altitude correction (because my analysis may imply a small tendency for my car to produce more HP given better weather--i.e., there is something of a negative correlation between density altitude and HP). I believe, at this moment, that all of what I am saying is consistent with my best unadjusted 1/4 times occurring when the weather tends to be "better" as indicate by the underscored torque values below, but with my best weather and altitude adjusted 1/4 times occurring when the weather tends to be worse. Somehow, this scenario doesn't seem to play right in my ears.
Good thinking earlier; I never gave up on finding a way to show whether or not your idea is valid. I should have thought of this simple approach earlier. What do you think now--given what's below? (DA = Density Altitude: Tq = Torque)
..DA....Max Tq
2151.3 242.4
2151.3 242.6
2085.6 245.9 237.850 (average last 3 similar DA-Tq values)
1771.5 235.1
1765.0 245.8
1765.0 247.4
1763.5 244.2
1763.5 246.0 239.580 (average last 5 similar DA-Tq values)
1722.4 244.0
1722.4 244.9
1695.0 241.1
1695.0 245.4 238.200 (average last 4 similar DA-Tq values)
1554.4 233.3
1554.4 245.3
1516.0 241.7
1516.0 246.0
1516.0 246.7
1509.3 240.0 238.700 (average last 6 similar DA-Tq values)
1415.4 247.2
1415.4 248.7 242.300 (average last 2 similar DA-Tq values)
1239.0 244.1
1223.2 244.5
1223.2 247.1
1223.2 247.5
1102.1 235.4
1102.1 249.4 241.350 (average last 6 similar DA-Tq values)
977.80 243.8
977.80 244.2
977.80 245.0
943.10 244.1
943.10 244.2
943.10 247.1 237.100 (average last 6 similar DA-Tq values)
801.30 244.9
801.30 252.1
801.30 253.1
787.90 248.3
787.90 248.3
787.90 251.4 243.317 (average last 6 similar DA-Tq values)
Maybe our really stupendous results should be presented after all.
EDIT: I calculated the moving-average maximum torque values below to get a smoothed "picture" of the sligthly negative correlation between my car's HP and density altitude. I calculated the averages by adding the next torque value (not numbered above) to the preceeding average calculation until I got to average 19. Then, I started dropping "oldest" torque values from the successive average calculations once I got to average 20. i.e., average 19 is based on torque values 01-19 (which, as mentioned, are not numbered above); average 20 is based on torque values 02-20, average 21 is based on torque values 03-21, etc., etc. When I got to average 38, I started leaving out the 2 "oldest" torque values for the next average calculation. The result is that average 44 is based on only the final five torque values.
Moving-Average
...Maximum
.....Torque
01. 236.7
02. 237.9
03. 238.4
04. 239.0
05. 239.0
06. 239.6
07. 239.1
08. 239.1
09. 239.1
10. 239.2
11. 238.8
12, 238.8
13. 238.9
14. 238.9
15. 238.7
16. 238.9
17. 239.1
18. 238.8
19. 238.9
20. 239.3
21. 239.1
22. 239.0
23. 239.0
24. 239.1
25. 239.4
26. 239.8
27. 239.6
28. 239.5
29. 239.3
30. 239.6
31. 239.3
32. 239.3
33. 239.4
34. 239.9
35. 240.3
36. 240.2
37. 240.6
38. 240.7
39. 240.8
40. 241.1
41. 240.5
42. 240.7
43. 241.5
44. 243.0
I think the NHRA corrections are a way to compare times for the same car or another car under varying weather conditions if no changes are made to the engine operating parameters.But if you review the weather conditions prior to a run and make mixture(jet )changes and timing changes accordingly, your time and speed will be less changed than the calculated corrections.However they still will not be the same as if the run was made at sea level.In effect this is what our modern cars are doing,changing mixture and timing according to weather conditions to somewhat negate the effects of weather.
Your torque data shows that the differences under various weather condiitions are not that great,which would indicate that the performance would not be as affected as indicated by the NHRA correction factors.