Just for Fun: Is the Step Still King in the Realm of the
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My Ride: 2005 BMW 545i, Silver Grey, Sport Package, R. Shades, Cold Pkg, Sat. Rad., Prem. Sound.
Originally Posted by Znod' post='312292' date='Jul 18 2006, 03:00 PM
I take it back. I can't download it. If others have trouble too, maybe you could try giving it a .jpg extension. I thought that giving it a .mov extension was clever, but doing so did not work for me--at least yet.
For every performance fans out there, this Excel spreadsheet is fun to use (and fairly accurate IMO
) when trying to figure 1/4 performance without all the math needed to explain it in a thread.
It should keep everyone attention.Let me know if you still can't download the file.
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My Ride: 2014 X5 xDrive 5.0 M Package Carbon Black Metallic/2008 M Roadster Imola Red
Originally Posted by Bimmer32' post='312213' date='Jul 18 2006, 01:03 PM
To get everyone back into the this conversation, I've created an Excel spreadsheet that essentially does everything the Internet calculators do but much more and easier for the average Joe to participate in this discussion. Everyone, download the attached Excel spreadsheet and have fun. Remember, it does not take into consideration such as environmental conditions, gearing, tire size, etc. Make sure to RENAME the extension from .MOV to .XLS
Attachment 21806
Attachment 21806
Distance (ft).....Time (sec)....Speed (mph).....RPM......Gear
....60'..................2.16...............37.12. .........6437......4.17
...330'.................5.70...............67.05.. ........4466......1.52
...660'.................8.68...............83.67.. ........5289......1.52
..1000'...............11.27...............94.61... .......5980......1.52
..1320'..............13.50.............100.75..........6369......1.52
What is most interesting about the above is how closely the ET comes to matching my average ET for my best 5 passes (13.50 versus 13.558--see below) when adjusted to a density altitude of 1600'--my actual altitude and the altitude used in the calculator calculations. The density altitude adjusted altitude assumes the standard conditions of 59 deg F air temp, 29.921 pressure in Hg, and 0 % relative humidity--which are not too far off from the weather data I use below. I will be doing another comparison using the standard conditons in the calculator. Here are the data related to the adjusted to 1600' ET for my best 5--with the key results in the last table in bold.
Calculate Density Altitude
Your results:
Air Temp 58.9 (?F)
Altimeter Setting 29.43 (in)
Dew Point 31.58 (?F)
Altitude 1600 (Feet)
Density Altitude 2618.5 (feet)
Correct 1/4 mi. Timeslip to Sea Level
Your results:
Density Altitude 2618.5 (feet)
Uncorrected ET 13.744 (sec)
Uncorrected MPH 102.9 (mph)
Corrected ET 13.317
Corrected MPH 106.271
Correct 1/4 mi. Timeslip to New Density Altitude
Your results:
E.T. 13.317 (sec)
Trap Speed 106.271 (mph)
Measured DA 0 (feet)
Corrected to 1600(feet) DA
Corrected ET 13.558 (sec)
Corrected Trap Speed 104.341 (mph)
Myy adjusted to 1600' trap speed does not agree with the SMOKEmUP e-Dragstrip calculator result. I am going to investigate farther, but note that the e-Dragstrip calculator has me at 6339 RPM in 3rd gear at the end of the 1/4--which is far from correct. Also, I am going to compare the calculator's result with my best pass adjusted to 1600' shortly.
OK, here are the results for my best pass. My ET agrees even more closely with its e-Dragstrip-calculator counterpart (13.50 versus 13.541). Still, a difference of .041 is surprising given the "weather differences."
Correct 1/4 mi. Timeslip to New Density Altitude
Your results:
E.T. 13.370 (sec)
Trap Speed 106.396 (mph)
Measured DA 500 (feet)
Corrected to 1600(feet) DA
Corrected ET 13.541 (sec)
Corrected Trap Speed 105.025 (mph)
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Originally Posted by Bimmer32' post='312313' date='Jul 18 2006, 04:08 PM
Right click the link and select Save As . . . if that is an option. Once on your computer, change the extension from .mov to .xls. This board does not allow me to upload an Excel extension.
For every performance fans out there, this Excel spreadsheet is fun to use (and fairly accurate IMO
) when trying to figure 1/4 performance without all the math needed to explain it in a thread.
It should keep everyone attention.
Let me know if you still can't download the file.
For every performance fans out there, this Excel spreadsheet is fun to use (and fairly accurate IMO
) when trying to figure 1/4 performance without all the math needed to explain it in a thread.
It should keep everyone attention.Let me know if you still can't download the file.
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Originally Posted by Znod' post='312352' date='Jul 18 2006, 04:12 PM
Nope. As I suggested, see if changing your upload extension to .jpg. Just attach another file. Maybe .mov will work for some.
Worked great for me. Downloaded it and changed the extension to xls as stated...
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Originally Posted by EBMCS03' post='312367' date='Jul 18 2006, 06:35 PM
Worked great for me. Downloaded it and changed the extension to xls as stated... 

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Originally Posted by EBMCS03' post='312367' date='Jul 18 2006, 06:35 PM
Worked great for me. Downloaded it and changed the extension to xls as stated... 

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Originally Posted by Bimmer32' post='312213' date='Jul 18 2006, 01:03 PM
Rightly so, there are many Internet calculators to use, but they have their shortcomings and are a bit off, like you say.
To get everyone back into the this conversation, I've created an Excel spreadsheet that essentially does everything the Internet calculators do but much more and easier for the average Joe to participate in this discussion. Everyone, download the attached Excel spreadsheet and have fun. Remember, it does not take into consideration such as environmental conditions, gearing, tire size, etc. Make sure to RENAME the extension from .MOV to .XLS
Attachment 21806
To get everyone back into the this conversation, I've created an Excel spreadsheet that essentially does everything the Internet calculators do but much more and easier for the average Joe to participate in this discussion. Everyone, download the attached Excel spreadsheet and have fun. Remember, it does not take into consideration such as environmental conditions, gearing, tire size, etc. Make sure to RENAME the extension from .MOV to .XLS
Attachment 21806
BMW 545i 3935 lbs 325 HP
Est. ET (sec.) 14.118
Est.Trap Speed (mph) 99.733
Curb wt (lbs) 3935
HP Rating (flywheel) 325
Trap Speed 99.733
ET Time 14.118
Driver wt (lbs) 165
Total Weight 4100
Est. ET (sec.) 14.118
Est.Trap Speed (mph) 99.733
Est. HP base on Trap Speed 327.522
Est. HP base on ET 326.514
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Originally Posted by EBMCS03' post='312301' date='Jul 18 2006, 03:49 PM
Uhhhh same thing for this board... did you check you settings?
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Originally Posted by doug_999' post='312641' date='Jul 19 2006, 09:40 AM
Help - What settings would need to be changed and where would I click to see all of my active threads? Thanks in advance!
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Originally Posted by Bimmer32' post='312213' date='Jul 18 2006, 01:03 PM
I figured out a much better way to show the correspondence between my best five results and the results of the SMOKEmUp calculator. First, here are all of my readily-available best-5 results that are comparable to the SMOKEmUP calculator data--and which have been adjusted for weather and altitude to 500'.
Adjusted for Weather and Altitude to 500'--Best Five Overall Tests:
..............................#1................#2 .............#3.............#4............#5...... ...Average
60'.........................2.059..........2.063.. ......2.071.........2.087.......2.076.........2.07 1
330'.......................5.806...........5.781.. .....5.813..........5.821......5.822.........5.808
1000'....................11.475.........11.420.... .11.479........11.463.....11.456.......11.459
1/4 Time...............13.495........13.499......13.48 0.......13.497......13.386.......13.469
1/4 Speed...........104.973......105.002.....105.104.. ...105.125....106.413....105.323
(Altitude?1,600?; DS-mode; DSC/DTC off; Pro RR meter; 1? rollout; 91 octane; Try for Minimal Wheel Spin using Minimal Brake Torquing)
Below are my calculator results. They differ from my earlier results because I set the (1) Converter Stall Speed factor to 1k RPM--which matches my launch RPM; (2) Torque Conversion factor to 1 since I found that my results are insensitive to this setting; and (3) Slippage factor to 1--which apparently is the most conservative possible setting. I also eliminated the "weather differences" from my prior approach by using 500' in the calculator and "standard" weather conditions. The result is as though my passes were made both at 500' and under standard conditions--which equates precisely to my adjusted 5-Best results given above. I now get the same average ET value from the calculator as before, but my terminal velocity is more realistic, and I am shown realistically to be in 4th gear at the end of the 1/4 and in second gear at 60'.
Now, here are my new calculator results. Please be happily impressed by the close correspondence between these results and my empirically derived Pro RR results--but especially the most important values--the ET values.
I am going to check farther to see how closely my speeds and RPM's agree with the calculator results for 60', 330', and 1000'.Distance (ft).....Time (sec)....Speed (mph).....RPM......Gear
....60'..................2.20...............37.13. .........3805......2.34
...330'.................5.66...............67.38.. ........4486......1.52
...660'.................8.60...............84.68.. ........5638......1.52
..1000'...............11.17...............94.68... .......6303......1.14
..1320'..............13.45...........101.83...........5084......1.52
Edit: I noticed that I accidentally used 4100 lbs above rather than 4150. Not much changes all the way up to 4200 lbs, but, regardless, I have included calculator results for 4150 and 4200 lbs below.
4150 lbs:
Distance (ft).....Time (sec)....Speed (mph).....RPM......Gear
....60'..................2.21...............36.95. .........3787......2.34
...330'.................5.68...............67.07.. ........4465......1.52
...660'.................8.64...............84.37.. ........5617......1.52
..1000'...............11.22...............94.42... .......6286......1.14
..1320'..............13.50...........101.47...........5066......1.52
4200 lbs:
Distance (ft).....Time (sec)....Speed (mph).....RPM......Gear
....60'..................2.22...............36.79. .........3771......2.34
...330'.................5.71...............66.85.. ........4450......1.52
...660'.................8.68...............84.06.. ........5597......1.52
..1000'...............11.27...............94.18... .......6270......1.14
..1320'..............13.56...........101.14...........5050......1.52
Edit:
Here are my average speeds at distances for my best 5 for comparison with the above tables. The correlations are pretty good. In concept, my recorded speeds actually should be a mile or so higher for comparability, and, thus, closer the the calculator's values, but they have not been adjusted for altitude and weather.
Speeds @ Distances
Test #......60'......330'.....1000'.....1320'*
34..........32.12...63.39....95.28....104.52
36..........33.10...63.41....95.20....105.54
38..........32.76...63.11....94.85....104.65
48..........33.10...63.30....95.30....105.10
53..........32.62...62.62....94.45....106.40
Average..32.74...63.17....95.02....105.24
*Trap Speed
And, here are my average RPM values at distances for my best 5 for comparison with the above tables. The correlations aren't bad for 1000' and 1320'. The calculator thinks I am in 2nd gear at 60'; however, the Pro RR thinks correctly that I am in 1st gear at 60'. I think the calculator error for 60' carries over to create calculator RPM errors for 330'.
RPM @ Distance
Test #.......60'......330'.....1000'.....1320'*
34...........6184....5382.....6121......5324
36...........6155....5524.....6132......5336
38...........6122....5495.....6120......5319
48...........6458....5924.....6580......5596 (not included in averge; something wrong with these RPM values)
53...........6015....5673.....6375......5251
Average...6119....5519....6187......5308
*RPM = average over trap


