# Drag Racing Tech - 1/4 mile vs 1/8

View Full Version : 1/4 mile vs 1/8

Shanna
12-30-2009, 09:53 AM
/ my car runs 8.20s at 91 with a 2.2 60 ft don't want to break the rear end. what kinda of time should it run in the 1/4 mile

buzz12586
12-30-2009, 11:51 AM
With that kind of mph in the 1/8th I can see it running 12.40-12.60's.

BlackScreaminMachine
12-30-2009, 12:05 PM
8.200 x 1.5555 = 12.751

This is considered the generally accepted calculation.

BlackScreaminMachine
12-30-2009, 12:06 PM
With that kind of mph in the 1/8th I can see it running 12.40-12.60's.

MPH is not an accurate guage of ET's.

It is essentially a Weight Vs. HP ratio at best.

and based on that rule, I wager she has a 6 speed transmission and some bolt on mods.

buzz12586
12-30-2009, 01:55 PM
I under MPH doesn't gauge ETs. I am just saying that the car is going to backhalf a lot better than it front halfs.

When my car was a 6speed it ran 12.32 1/4 with a 7.98 1/8th on a 1.89 60ft

12.32/7.98 = 1.543

Now with the A4 it is 12.08 1/4 with a 7.66 1/8th on a 1.63 60ft

12.08/7.66 = 1.577

91mph is a ton of speed for an 8.20 1/8th mile time.

RARON455
12-30-2009, 05:03 PM
Yeah, that is alot of MPH for an 8.2 pass, especially with a 2.2 60ft. Normally a et of 8.20 would be around 84ish.

Shanna
12-30-2009, 06:07 PM
it does have alot of mods. i baby it out of the hole it is a m6.iam runing drag rad. if i launch it do you think i will break the rear end

tee-boy
12-30-2009, 06:42 PM
I always went off rule of .1 in 60ft is .2 in 1/4 mile and .1 in the 1/8th is .15 in the 1/4 mile. You could interpolate the ratios inbetween 330, 660 etc... But it isn't exactly linear.

Acceleration is a second order function (non linear). Velocity is a primary order function (linear).

RARON455
12-30-2009, 07:19 PM
it does have alot of mods. i baby it out of the hole it is a m6.iam runing drag rad. if i launch it do you think i will break the rear end

MODS,,,,DRAG Radials,,,,, HMMM Lets say,,,, absolutely
especially with it being a 6 speed, one good clutch dump and you will need a tow truck.