piston pounder

Does anyone on this forum know how to correct my 1/4mile time for elevation?. ok heres the low down-
-r/t. .608
-60' . 2.436
-330 .6.776
-1/8 .10.500
-mph .65.97
-1000 .13.712
-1/4 .16.472
-mph .81.55
Ran at Bandimere Speedway in Denver Colorado, elvation is 5,280 ft. above sea level. Thanks!.

piston pounder

ok, someone out there has to now how to convert this!. come-on fellow rotary heads!

mar3

iTrader: (8)

I'm assuming you mean to sea-level, but even then, it's not going to be that big of a difference. I'd guesstimate 1/8th at 10.4 and 1/4 at 16.25-16.3...

rx7 Nut

I asked that question a few months ago and got this link to an NHRA site that had this chart. Find your altitude and muliply your time by the 2nd column and mutliply your mph by the 3rd column. It helped me a lot cause I'm at 3500 feet so it made a difference.

Altitude 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

rx7 Nut

Hey I just converted your time. 15.37 pretty good time. what do you drive and what mods?

piston pounder

Hey thanks alot for the info!. I knew someone could help me out!. 15.37, thats a pretty good time for this stock port motor!. Well here you go on my info- stock port 12a with aprox. 120,000 miles on it
-45mm weber sidedraft carb from mazdatrix
-mindtrain stageV race exhaust
-bone yard electric fan from a fiero
-only one belt running the alt./waterpump
-stock fuel pump at?. pressure (gonna replace it soon)
-american racing 13inch wheels with dunlop 205/60r13 tires

WackyRotary

Just figure out your RAD(Relative Air Density) at different alitudes. Air pressure differs day to day even at alitudes. All depends how acurate you want to be.