To convert your Quarter Mile ET and MPH to sea level times, multiply applicable factor times your ET or MPH.
Select
the appropriate chart for your application:
Stock and Mildly Modified NA Engines
Extensively Modified NA Engines
Extensively Modified Super/Turbocharged
Engines
Stock
and Mildly Modified Naturally Aspirated Engines
| Altitude (in feet) | Elapsed Time Factor | MPH Factor |
| 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 |
| 5600 | .9302 | 1.0745 |
| 5700 | .9289 | 1.0759 |
| 5800 | .9276 | 1.0773 |
| 5900 | .9263 | 1.0787 |
| 6000 | .9250 | 1.0801 |
Extensively
Modified Naturally Aspirated Engines
| Altitude (in feet) | Elapsed Time Factor | MPH Factor |
| 1200 | .9934 | 1.0068 |
| 1300 | .9922 | 1.0078 |
| 1400 | .9911 | 1.0089 |
| 1500 | .9899 | 1.0100 |
| 1600 | .9888 | 1.0111 |
| 1700 | .9876 | 1.0122 |
| 1800 | .9865 | 1.0132 |
| 1900 | .9853 | 1.0143 |
| 2000 | .9842 | 1.0154 |
| 2100 | .9830 | 1.0165 |
| 2200 | .9819 | 1.0175 |
| 2300 | .9807 | 1.0186 |
| 2400 | .9796 | 1.0197 |
| 2500 | .9784 | 1.0208 |
| 2600 | .9773 | 1.0218 |
| 2700 | .9761 | 1.0229 |
| 2800 | .9750 | 1.0240 |
| 2900 | .9738 | 1.0251 |
| 3000 | .9727 | 1.0262 |
| 3100 | .9715 | 1.0272 |
| 3200 | .9704 | 1.0283 |
| 3300 | .9692 | 1.0294 |
| 3400 | .9681 | 1.0305 |
| 3500 | .9669 | 1.0315 |
| 3600 | .9658 | 1.0326 |
| 3700 | .9646 | 1.0337 |
| 3800 | .9635 | 1.0348 |
| 3900 | .9623 | 1.0358 |
| 4000 | .9612 | 1.0369 |
| 4100 | .9600 | 1.0380 |
| 4200 | .9589 | 1.0391 |
| 4300 | .9577 | 1.0401 |
| 4400 | .9566 | 1.0412 |
| 4500 | .9554 | 1.0423 |
| 4600 | .9543 | 1.0434 |
| 4700 | .9531 | 1.0445 |
| 4800 | .9520 | 1.0455 |
| 4900 | .9508 | 1.0466 |
| 5000 | .9497 | 1.0477 |
| 5100 | .9485 | 1.0488 |
| 5200 | .9474 | 1.0498 |
| 5300 | .9462 | 1.0509 |
| 5400 | .9451 | 1.0520 |
| 5500 | .9439 | 1.0531 |
| 5600 | .9428 | 1.0541 |
| 5700 | .9416 | 1.0552 |
| 5800 | .9405 | 1.0563 |
| 5900 | .9393 | 1.0574 |
| 6000 | .9382 | 1.0585 |
Extensively
Modified Supercharged and Turbocharged Engines
| Altitude (in feet) | Elapsed Time Factor | MPH Factor |
| 1200 | .9967 | 1.0034 |
| 1300 | .9961 | 1.0039 |
| 1400 | .9955 | 1.0045 |
| 1500 | .9950 | 1.0050 |
| 1600 | .9944 | 1.0055 |
| 1700 | .9938 | 1.0061 |
| 1800 | .9932 | 1.0066 |
| 1900 | .9927 | 1.0072 |
| 2000 | .9921 | 1.0077 |
| 2100 | .9915 | 1.0082 |
| 2200 | .9909 | 1.0088 |
| 2300 | .9904 | 1.0093 |
| 2400 | .9898 | 1.0098 |
| 2500 | .9892 | 1.0104 |
| 2600 | .9886 | 1.0109 |
| 2700 | .9881 | 1.0115 |
| 2800 | .9875 | 1.0120 |
| 2900 | .9869 | 1.0125 |
| 3000 | .9863 | 1.0131 |
| 3100 | .9858 | 1.0136 |
| 3200 | .9852 | 1.0142 |
| 3300 | .9846 | 1.0147 |
| 3400 | .9840 | 1.0152 |
| 3500 | .9835 | 1.0158 |
| 3600 | .9829 | 1.0163 |
| 3700 | .9823 | 1.0168 |
| 3800 | .9817 | 1.0174 |
| 3900 | .9812 | 1.0179 |
| 4000 | .9806 | 1.0185 |
| 4100 | .9800 | 1.0190 |
| 4200 | .9794 | 1.0195 |
| 4300 | .9789 | 1.0201 |
| 4400 | .9783 | 1.0206 |
| 4500 | .9777 | 1.0212 |
| 4600 | .9771 | 1.0217 |
| 4700 | .9766 | 1.0222 |
| 4800 | .9760 | 1.0228 |
| 4900 | .9754 | 1.0233 |
| 5000 | .9748 | 1.0238 |
| 5100 | .9743 | 1.0244 |
| 5200 | .9737 | 1.0249 |
| 5300 | .9731 | 1.0255 |
| 5400 | .9725 | 1.0260 |
| 5500 | .9720 | 1.0265 |
| 5600 | .9714 | 1.0271 |
| 5700 | .9708 | 1.0276 |
| 5800 | .9702 | 1.0281 |
| 5900 | .9697 | 1.0287 |
| 6000 | .9691 | 1.0292 |
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