I have only ran my car a few times at the local 1/8th track because the 1/4 is a long way away. My times are poor but I will be working on that this spring aswell as making the trips to the 1/4 but I'm just curous as to what gains in the eighth of a mile would equal in the quarter. Say I get a tenth from a good CAI, would should I expect in the quarter? Thanks for clearing it up for this newbie.

 

this is only MY experience. but when i went from 8.8 to 8.1 in the 1/8, my 1/4s wwent from 13.7s to 12.7s. so, thats .7 in the 1/8 and a sec in the 1/4. but, that time was spinning so my 1/8 prolly should have been a little faster.

i would say a better way to look at it would be on avg. that your 1/8 will usually be .2-.4 slower than your 1/4. thats in a gain. so, if you go from a 14.3 1/4 and 9.2 1/8, to a 13.5 1/4, then your 1/8 will prolly be around a 8.7 or so.

is this making sense? prolly not.... sorry



and since when was 1000+ posts considered a newbie??




jon

 

I usually go by a general rule. For every tenth you drop in the eigth you should/could drop .15 or at best 2 tenths in the quarter. That is just me. Some people pick up less and some pick up more. I guess it is determined a little by what mods you do.

 

I was running 8.6 in the 1/8 and running 13.2 in the 1/4...ran on slicks and lowered my 1/8 mile ETs to 8.2 and my 1/4 to 12.7. I gained ~ 5 tenths in the quarter from a 4 tenth gain in the 1/8.

 

use this method to find out your 1/4 times when I dont run 1/4 (track is 2hours away)so I only get a few 1/4 mile passes a year.. but here it goes its real easy. I run 7.69 8th X that by 1.56=11.99 for me its only .03off..my NA times are .001off.. so I say it is very accurate... hope this helps

 

It is very close to .1 off the eighth equaling .15 in the 1/4. I have some calculators that I've made and are mathematically sound:

For ET:

For Sticks:

(1/8mi ET)
---------------------------------------------
( 2.731 x 60' time + 58.917 ) / 100

For Autos:

(1/8mi ET)
---------------------------------------------
( 2.307 x 60' time + 59.656) / 100

To find MPH's:

For Sticks:

(1/8mi MPH)/.79485

for Autos:

(1/8mi MPH)/.79762

I made these because all the calculators they use on the internet do not use 60' time at all, making them very innacurate unless you run a 60' time that they already have built in for their calculator.

EXA)
Car A runs 60' of 2.0 and 8.5 1/8
Car B runs 60' of 2.4 and 8.5 1/8

By their calculators they will run identical 1/4 mi times but in reality car B should be faster than they say.

Get it?