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