black_knight

iTrader: (1)

I read these threads where someone runs such-and-such in the 1/8th, and I'm like "okay, now WTF does that mean?"

How's about putting a sticky up with conversion calculators?

Smokinstorm

iTrader: (5)

Unfortunately there's no one single conversion factor that works with all cars. My SS works out to 1.575 but it's because it 60's well so it ET's well in the 1/8th. 1.59-->7.66@88.5-->12.07@111.82 in my case. Other cars with much more horsepower but street tires may run similar times in the 1/8th compared to my car but will be much quicker by the 1320' mark. Most cars that don't have wheelspin factor between 1.55 and 1.58 but there will always be those outside this window. Hope this helps you with us 1/8th milers.

black_knight

iTrader: (1)

I think it helps me to understand there is no direct conversion, LOL.

gator's 99TA

iTrader: (2)

1/8th mile ET x 1.57 is a pretty damn good conversion for nitrous and n/a cars running mid 8s and higher.

AOC

The pass I've made with set of street radials...

1/8 = 7.453@99.30
1/4 = 11.398@126.36

Using 1.57 factor to calculate 1/8 time to 1/4 time.

7.453 x 1.57 = 11.701

So, that is .303 difference, bit more than close, imo.

Smokinstorm

iTrader: (5)

Your car with street tires will fall outside the 1.55-1.58 window because you ran a truly crappy 1/8th mile time compared to your MPH. Your car is an example I was talking about that ET's similar to mine in the 1/8th mile but doesn't even come close in a 1/4 mile, you being much quicker and faster obviously. This is exactly why no one conversion factor will work on every car. However, if you put a set of slicks on your car, hook from the line and compare your 1/8th to 1/4 mile set up like that I'll bet your conversion factor will fall right in line. As was mentioned above, 1.57 comes pretty darned close on most cars that dead hook from the line. You guys with slicks, ET Streets, QTP's, etc that dead hook post up your incrementals and see if they don't fall between 1.55 and 1.58. I'm certainly not trying to spread misinformation here. I'm just trying to help out the 1/4 milers like the original poster that never pay attention to their 1/8th mile times so you can see where we 1/8th milers stand in the grand scheme of things.

gator's 99TA

iTrader: (2)

i ran consistent 7.0 @ 99 mph and 10.94 @ 1222

7.0 x 1.57 = 10.99

AOC, i have a feeling your run is not linear. i bet you spray after your initial launch.

AOC

It wasn't good but not crappy. On that pass, I cut 1.820 60' time but yeah, I had lot of spin all the way to 3rd gear. I understand what you are getting at though.

gator's 99TA
Yes. Normally, I spray right after 2nd gear but on that pass, I did spray right after the launch.

jay_99z

iTrader: (5)

This one has worked out pretty close for me. http://www.wallaceracing.com/eigth-t...conversion.php

More calculators http://www.wallaceracing.com/Calculators.htm

gator's 99TA

iTrader: (2)

well the 1.57 to 1.575 multiplication works for just about every car on this site. the only real exceptions are turbo or centrifugal blower cars or cars built specifically for 1/8th mile racing

Villain281H

iTrader: (5)

I think conversions have a lot of gray area, and every car is different depending on set-up, even if you are dead-hooking.

For example on my Nova:

7.221 @ 93.79 mph 1/8 mile x 1.57 = 11.33
7.221 @ 93.79 mph 1/8 mile x 1.575 = 11.37
7.221 @ 93.79 mph 1/8 mile x 1.58 = 11.409 (closest to the 11.42 I actually ran).

Versus my Formula:

8.325 @ 85.80 mph 1/8 mile x 1.58 = 13.15
8.325 @ 85.80 mph 1/8 mile x 1.57 = 13.07
8.325 @ 85.80 mph 1/8 mile x 1.56 = 12.98
8.325 @ 85.80 mph 1/8 mile x 1.55 = 12.90 (closest to the 12.89 I actually ran).

Remember, it's just a guess and gives you what COULD BE your 1/4 time.

Derek