In fact, here is the correction table FOR ALTITUDE ONLY with an explanation on how to correct it. Why don't we do this and repost our corrected numbers (use of the calculator is FAR better as it provides a true SAE correction for elevation, temperature, atmospheric pressure, and humidity) but since not many people are going to want to sign up just to use a calculator, I provide the following):

NHRA Elevation Correction Factor
To convert your timeslip ET and MPH to sea level. Multiply applicable factor times your ET or MPH.

(Example: You ran a 13.8 @ 100 MPH at 5000' elevation track. The correction factors are .9367 and 1.0661 for 5000'. (13.8 * .9367) = 12.93 , (100 * 1.0661) = 106.61 MPH. So the correct timeslip would be 12.93 @ 106.61 MPH.)

Altitude above Sea Level (Feet) | Elapsed Time Factor (ET) | Trap Speed Factor (MPH)
1200 .9874 1.0129
1300 .9861 1.0143
1400 .9848 1.0157
1500 .9835 1.0171
1600 .9822 1.0185
1700 .9809 1.0199
1800 .9796 1.0213
1900 .9783 1.0227
2000 .9770 1.0241
2100 .9757 1.0255
2200 .9744 1.0269
2300 .9731 1.0283
2400 .9718 1.0297
2500 .9705 1.0311
2600 .9692 1.0325
2700 .9679 1.0339
2800 .9666 1.0353
2900 .9653 1.0367
3000 .9640 1.0381
3100 .9627 1.0395
3200 .9614 1.0409
3300 .9601 1.0423
3400 .9588 1.0437
3500 .9575 1.0451
3600 .9562 1.0465
3700 .9549 1.0479
3800 .9536 1.0493
3900 .9523 1.0507
4000 .9510 1.0521
4100 .9497 1.0535
4200 .9484 1.0549
4300 .9471 1.0563
4400 .9458 1.0577
4500 .9445 1.0591
4600 .9432 1.0605
4700 .9419 1.0619
4800 .9406 1.0633
4900 .9393 1.0647
5000 .9380 1.0661
5100 .9367 1.0675
5200 .9354 1.0689
5300 .9341 1.0703
5400 .9328 1.0717
5500 .9315 1.0731

 

Smokemup would be great if I had the Temp, Dew Point, and Altimeter Setting. Or if that table went down to 450'




2003 G35 Coupe 6MT/Black/Graphite/15% tint/6 wire GroundingGear™

 

humidity, and barometric pressure do NOT affect the times that much. Altitude is the biggest factor. So just punch in the altitudea and estimate temperature (assume normal barometric pressure and humidity, or estimate the latter from weather reports)

Gurgen

 

Actually, we are talking about the altimeter setting (which is the barometric pressure if that elevation was reduced to sea level). So, you can pretty safely use 29.92 inch Hg (not sure why SAE decided to standardize it to 29.35). You can basically get the "barometer readings" from the weather report.

EDIT: Here is your corrected run:

Air Temp 77
Dew Point 0
Altitude 450 (Ft)
Altimeter Setting 29.92 (In Hg)
Uncorrected ET 14.27 (sec)
Uncorrected MPH 101 (mph)

Corrected ET 14.29
Corrected MPH 100.85

<P ID="edit"><FONT class="small"><EM>Edited by gurgenpb on 03/26/04 09:11 AM.</EM></FONT></P>

 

up-date,

last Sat I ran a 12.4@115 60ft-2.0sec


Carlito's 12.4@115mph G35