New G-Tech Pros SS G-Meter Discussion
#101
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Originally Posted by EuroCarFan' post='225554' date='Jan 17 2006, 03:37 PM
Looking back at one of your initial posts, you used a test weight from Car & Driver, 4150. I believe the driver for that test car is 200lbs so I'll subtract 70 to get 4080 and just round up to get 4100 (I don't have comfort seats). I don't know of any public scales around here either.
I'll definitely stick to the 12" rollout but will probably do some 0 rollouts later on as well. My two main objectives with using the GT2 is 1) to compare my results with you, Grogan, Realtyman and the drag strip and 2) to measure changes (hopefully positive) in performance before and after my Dinan upgrades. For the latter, I'm looking at possibly 3 sets of data: 1) currently stock, 2) w/Dinan CAI, throttle body, and exhaust and 3) with Dinan MAF and ECU programming.
If all our times are accurate and consistent, I would hope that with all those mods, that I can definitely break the 5.0 barrier.
I'll definitely stick to the 12" rollout but will probably do some 0 rollouts later on as well. My two main objectives with using the GT2 is 1) to compare my results with you, Grogan, Realtyman and the drag strip and 2) to measure changes (hopefully positive) in performance before and after my Dinan upgrades. For the latter, I'm looking at possibly 3 sets of data: 1) currently stock, 2) w/Dinan CAI, throttle body, and exhaust and 3) with Dinan MAF and ECU programming.
If all our times are accurate and consistent, I would hope that with all those mods, that I can definitely break the 5.0 barrier.
#102
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Excuse me sirs, this pupil has another point to discuss. With regards to Pitch and Roll characteristics, I had just installed a set of KW Variant 2 Coilovers today so my car would probably be classified as having a stiff suspension.
Sooo...I was thinking of setting my Pitch to about 1.6-1.7 vs the default of 2.0. As a point of reference the Z06's pitch is 1.5. For Roll the default is 3.0 so I'll set mine to about 2.7.
What effects do these settings have on acceleration, if any? I also don't see how they can affect horsepower calculations either. I assume they're just for the G-Timer functions?
Sooo...I was thinking of setting my Pitch to about 1.6-1.7 vs the default of 2.0. As a point of reference the Z06's pitch is 1.5. For Roll the default is 3.0 so I'll set mine to about 2.7.
What effects do these settings have on acceleration, if any? I also don't see how they can affect horsepower calculations either. I assume they're just for the G-Timer functions?
#103
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Originally Posted by EuroCarFan' post='225783' date='Jan 17 2006, 11:50 PM
Excuse me sirs, this pupil has another point to discuss. With regards to Pitch and Roll characteristics, I had just installed a set of KW Variant 2 Coilovers today so my car would probably be classified as having a stiff suspension.
Sooo...I was thinking of setting my Pitch to about 1.6-1.7 vs the default of 2.0. As a point of reference the Z06's pitch is 1.5. For Roll the default is 3.0 so I'll set mine to about 2.7.
What effects do these settings have on acceleration, if any? I also don't see how they can affect horsepower calculations either. I assume they're just for the G-Timer functions?
Sooo...I was thinking of setting my Pitch to about 1.6-1.7 vs the default of 2.0. As a point of reference the Z06's pitch is 1.5. For Roll the default is 3.0 so I'll set mine to about 2.7.
What effects do these settings have on acceleration, if any? I also don't see how they can affect horsepower calculations either. I assume they're just for the G-Timer functions?
#104
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Originally Posted by EuroCarFan' post='225783' date='Jan 17 2006, 11:50 PM
Excuse me sirs, this pupil has another point to discuss. With regards to Pitch and Roll characteristics, I had just installed a set of KW Variant 2 Coilovers today so my car would probably be classified as having a stiff suspension.
Sooo...I was thinking of setting my Pitch to about 1.6-1.7 vs the default of 2.0. As a point of reference the Z06's pitch is 1.5. For Roll the default is 3.0 so I'll set mine to about 2.7.
What effects do these settings have on acceleration, if any? I also don't see how they can affect horsepower calculations either. I assume they're just for the G-Timer functions?
Sooo...I was thinking of setting my Pitch to about 1.6-1.7 vs the default of 2.0. As a point of reference the Z06's pitch is 1.5. For Roll the default is 3.0 so I'll set mine to about 2.7.
What effects do these settings have on acceleration, if any? I also don't see how they can affect horsepower calculations either. I assume they're just for the G-Timer functions?
I don,t think either the pitch or roll has any effect on horsepower readings.
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I looked at the manual again and it says that besides for the 0-60 times, changing the pitch won't significantly affect 60 foot times but will affect 1/8 and 1/4 mile times. It doesn't say by how much.
#106
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Originally Posted by EuroCarFan' post='225959' date='Jan 18 2006, 12:07 PM
I looked at the manual again and it says that besides for the 0-60 times, changing the pitch won't significantly affect 60 foot times but will affect 1/8 and 1/4 mile times. It doesn't say by how much.
#108
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Originally Posted by EuroCarFan' post='225985' date='Jan 18 2006, 12:53 PM
Yep, I saw that as well.
Still waiting for a dry day...............
Still waiting for a dry day...............
#109
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[/quote]
Hi Guys:
I became interested in comparing rates of acceleration, in general, and also in using these data to try to infer Step. shifting abilities. So, first, I rearranged grogan?s formula so that it could be used to estimate the average 1/8 mile time for the big 3 US auto mag tests.
Znod Est average ? time = 660/((((.6(Est 1/4 Spd - Act 1/8 Spd) + Act 1/8 Spd)/94.6)138.75)) + Act average 1/8 time = 13.4971 (i.e., given Est average ? Spd of 103 and Act average 1/8 results)
Znod Est average 1/8 time = Act average 1/4 time - (660/((((.6(Act 1/4 Spd - Est 1/8 Spd) + Est 1/8 Spd)/94.6)138.75))) = 8.71 (i.e., given Est average 1/8 Spd and ?Act? average ? results)
Mags Est average 1/8 time = Act average 1/4 time - (660/((((.6(Act 1/4 Spd - Est 1/8 Spd) + Est 1/8 Spd)/94.6)138.75))) = 8.943 (i.e., given Est average 1/8 Spd of 80.5 and Act average ? results)
Given the mag. value of 8.943, the following table for the mags became possible (all tables given below, including the addition of limited (mags) and suboptimal (Znod and possibly grogan) 90 MPH data, are attached in a more readable format):
Datum/Mag1/Mag2/Mag3/Ave/Change/Rate of Acceleration
1/8 Mile Time x.xx x.xx x.xx 0.18 8.33
0-80 8.90 8.40 9.00 8.77 1.62 6.19
0-70 7.10 7.20 7.15 1.78 5.61
0-60 5.40 5.20 5.50 5.37 1.32 7.59
0-50 4.00 4.10 4.05 1.15 8.70
0-40 2.80 2.90 3.00 2.90 1.15 8.70
0-30 1.60 1.90 1.75 0.65 15.38
0-20 1.10 1.10 0.78 12.82
0-10 (Assumed) 0.32 0.32 31.25
0-0 0.00
Similar tables for Znod and grogan, repectively, are given below:
Datum/Znod Test 1/Znod Test 2/Znot Test 3/Test 4/Test5/Ave/Change/Rate of Acceleration
1/8 Mile Time 8.78 8.71 8.71 8.71 8.73 8.73 0.07 5.14
0-80 8.72 8.65 8.65 8.60 8.67 8.66 1.85 5.42
0-70 6.82 6.75 6.82 6.90 6.77 6.81 1.67 6.00
0-60 5.14 5.07 5.22 5.22 5.07 5.14 1.25 7.99
0-50 3.89 3.82 3.92 3.95 3.88 3.89 1.08 9.26
0-40 2.82 2.76 2.83 2.87 2.78 2.81 1.11 8.98
0-30 1.72 1.65 1.70 1.72 1.70 1.70 0.75 13.40
0-20 0.97 0.89 1.00 0.95 0.95 0.95 0.66 15.05
0-10 0.32 0.25 0.30 ,27 0.28 0.29 0.29 34.78
0-0 0.00
Datum/grogan Test 1/grogan Test 2/grogan Test 3/grogan Test 3/Ave/Change/Rate of Acceleration
1/8 Mile Time 8.75 8.75 8.83 8.83 8.79 0.52 2.83
0-80 8.12 8.05 8.45 8.45 8.27 1.61 6.21
0-70 6.55 6.52 6.78 6.78 6.66 1.57 6.39
0-60 5.03 5.00 5.17 5.17 5.09 1.24 8.08
0-50 3.83 3.83 3.88 3.88 3.86 1.05 9.55
0-40 2.80 2.83 2.80 2.80 2.81 1.05 9.55
0-30 1.73 1.85 1.73 1.73 1.76 0.74 13.47
0-20 1.02 1.05 1.00 1.00 1.02 0.68 14.65
0-10 0.35 0.33 0.33 0.33 0.34 0.34 29.85
0-0 0.00
Comparing the final columns from the three tables gives the following:
Datum/Rate of Acceleration-Mags/Rate of Acceleration-Znod/Rate of Acceleration grogan
1/8 Mile Time 8.33 5.14 2.83
0-80 6.19 5.42 6.21
0-70 5.61 6.00 6.39 Shift to 3rd
0-60 7.59 7.99 8.08
0-50 8.70 9.26 9.55
0-40 8.70 8.98 9.55 Shift to 2nd
0-30 15.38 13.40 13.47
0-20 12.82 15.05 14.65
0-10 31.25 34.78 29.85
Observations:
1. The 40-50 rates of acceleration are the same as the 30-40 rates of acceleration for the mags and grogan?which suggests good Steptronic shifting. For Znod the 40-50 rate of acceleration exceeds the 30-40 rate suggesting that the shift to 2nd is hurting Znod?s times. The comparison of the 0-40 rates of grogan (9.55) and Znod (8.98) also suggests that Znod?s times may be affected negatively by the shift to 2nd. Indeed, one might conclude that suboptimal Znod shifts to 2nd lead to grogan?s faster speeds, but not quicker times, through the 1/8. In this regard, Znod's larger early rates, and roughly comparable rates through 70, lead to his quicker 1/8 mile times.
2. Comparisons of the 60-70 and 70-80 data provide no obvious basis for inferring that the shifts from 2nd to 3rd are hurting either Znod or grogan.
3. Znod?s set of rates of acceleration do not appear to contain any ?unusual? results. On the other hand, the other two sets may contain two ?unrealistic? values?8.33 (too "fast") and 2.83 (too "slow"). Note that the rates from 80 through the 1/8 are not accurate in general because the GT2 calculates 1/8 times over the trap. Also, note that the 90 mile rates are calculated from 80 to 90 (and not the the 1/8 speed to 90.
4. The sets for Znod and Grogan provide another way of looking at some things we already have observed. Znod accelerates more rapidly to about 40 and then grogan begins to gain?possibly because of suboptimal shifting to 2nd of Znod?s car.
Happy thinking.
#110
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I became interested in comparing rates of acceleration, in general, and also in using these data to try to infer Step. shifting abilities. So, first, I rearranged grogan?s formula so that it could be used to estimate the average 1/8 mile time for the big 3 US auto mag tests.
Znod Est average ? time = 660/((((.6(Est 1/4 Spd - Act 1/8 Spd) + Act 1/8 Spd)/94.6)138.75)) + Act average 1/8 time = 13.4971 (i.e., given Est average ? Spd of 103 and Act average 1/8 results)
Znod Est average 1/8 time = Act average 1/4 time - (660/((((.6(Act 1/4 Spd - Est 1/8 Spd) + Est 1/8 Spd)/94.6)138.75))) = 8.71 (i.e., given Est average 1/8 Spd and ?Act? average ? results)
Mags Est average 1/8 time = Act average 1/4 time - (660/((((.6(Act 1/4 Spd - Est 1/8 Spd) + Est 1/8 Spd)/94.6)138.75))) = 8.943 (i.e., given Est average 1/8 Spd of 80.5 and Act average ? results)
Given the mag. value of 8.943, the following table for the mags became possible:
Datum/Mag1/Mag2/Mag3/Ave/Change/Rate of Acceleration
1/8 Mile Time x.xx x.xx x.xx 0.18 8.33
0-80 8.90 8.40 9.00 8.77 1.62 6.19
0-70 7.10 7.20 7.15 1.78 5.61
0-60 5.40 5.20 5.50 5.37 1.32 7.59
0-50 4.00 4.10 4.05 1.15 8.70
0-40 2.80 2.90 3.00 2.90 1.15 8.70
0-30 1.60 1.90 1.75 0.65 15.38
0-20 1.10 1.10 0.78 12.82
0-10 (Assumed) 0.32 0.32 31.25
0-0 0.00
Similar tables for Znod and grogan, repectively, are given below:
Datum/Znod Test 1/Znod Test 2/Znot Test 3/Test 4/Test5/Ave/Change/Rate of Acceleration
1/8 Mile Time 8.78 8.71 8.71 8.71 8.73 8.73 0.07 5.14
0-80 8.72 8.65 8.65 8.60 8.67 8.66 1.85 5.42
0-70 6.82 6.75 6.82 6.90 6.77 6.81 1.67 6.00
0-60 5.14 5.07 5.22 5.22 5.07 5.14 1.25 7.99
0-50 3.89 3.82 3.92 3.95 3.88 3.89 1.08 9.26
0-40 2.82 2.76 2.83 2.87 2.78 2.81 1.11 8.98
0-30 1.72 1.65 1.70 1.72 1.70 1.70 0.75 13.40
0-20 0.97 0.89 1.00 0.95 0.95 0.95 0.66 15.05
0-10 0.32 0.25 0.30 ,27 0.28 0.29 0.29 34.78
0-0 0.00
Datum/grogan Test 1/grogan Test 2/grogan Test 3/grogan Test 3/Ave/Change/Rate of Acceleration
1/8 Mile Time 8.75 8.75 8.83 8.83 8.79 0.52 2.83
0-80 8.12 8.05 8.45 8.45 8.27 1.61 6.21
0-70 6.55 6.52 6.78 6.78 6.66 1.57 6.39
0-60 5.03 5.00 5.17 5.17 5.09 1.24 8.08
0-50 3.83 3.83 3.88 3.88 3.86 1.05 9.55
0-40 2.80 2.83 2.80 2.80 2.81 1.05 9.55
0-30 1.73 1.85 1.73 1.73 1.76 0.74 13.47
0-20 1.02 1.05 1.00 1.00 1.02 0.68 14.65
0-10 0.35 0.33 0.33 0.33 0.34 0.34 29.85
0-0 0.00
Comparing the final columns from the three tables gives the following:
Datum/Rate of Acceleration-Mags/Rate of Acceleration-Znod/Rate of Acceleration grogan
1/8 Mile Time 8.33 5.14 2.83
0-80 6.19 5.42 6.21
0-70 5.61 6.00 6.39 Shift to 3rd
0-60 7.59 7.99 8.08
0-50 8.70 9.26 9.55
0-40 8.70 8.98 9.55 Shift to 2nd
0-30 15.38 13.40 13.47
0-20 12.82 15.05 14.65
0-10 31.25 34.78 29.85
Observations:
1. The 40-50 rates of acceleration are the same as the 30-40 rates of acceleration for the mags and grogan?which suggests good Steptronic shifting. For Znod the 40-50 rate of acceleration exceeds the 30-40 rate suggesting that the shift to 2nd is hurting Znod?s times. The comparison of the 0-40 rates of grogan (9.55) and Znod (8.98) also suggests that Znod?s times may be affected negatively by the shift to 2nd. Indeed, one might conclude that suboptimal Znod shifts to 2nd lead to grogan?s faster times through the 1/8.
2. Comparisons of the 60-70 and 70-80 data provide no obvious basis for inferring that the shifts from 2nd to 3rd are hurting any ?car.?
3. Znod?s set of rates of acceleration do not appear to contain any ?unusual? results. On the other hand, the other two sets may contain two ?unrealistic? values?8.33 (too "fast") and 2.83 (too "slow").
4. The sets for Znod and Grogan provide another way of looking at some things we already have observed. Znod accelerates more rapidly to about 40 and then grogan gains an advantage?possibly because of suboptimal shifting to 2nd of Znod?s car.
I hope I am not presenting these data prematurely. Additional ?conclusions? probably are possible. Let?s all think about the data and see if we can come up with others. I am tired now and don?t want to deal with the data any more for a while. Ill be editing for a while though--undoubtedly.
Happy thinking.
P.S. Tomorrow I am going to see if I can somewhat easily attach the tables so that they are more readable.
[/quote]
Wow I need to study for awhile to see if I comprehend it all.The one thing that am confused about is the rate of acceleration you developed for the 1/8.I think I am grasping the rest of the numbers.I 'm also tired maybe the 1/8 data will come to me after I study it some more.