1/8 to 1/4 conversions?

[grandkodiak]

All the tracks I've ever been to are 1/4 miles, and all the numbrs i've ever cared about when researching acceleration where 1/4 times and speed... but i've seen a few 1/8 spots pop up and i know a few roads that have ample room to run a solid 1/8th.... but... i hav no idea how to relate the times/speeds of an 8th to a 1/4. like 14 quarter is bare bone limit for a fast car... 13's respectible, 12's very respectable... 10's highest most can expect with a street car, anything below that they are posting fulltime drag car times down to 8 which is balls fast top of the top.

[jking]

There is no set formula becasue all cars run differently. Some make up their time in the launch, some run harder through the 1/8th and fall off. Some pull harder towards the big end of the track, like LS1's for instance.

There are calculators you can find on line that will get you close though...

[jking]

Most of the time, low 8's come out to mid to high 12's.

low 9's come out to low 14's.

[tnthub]

A very general calulation is your 1/8 mile ET times 1.55. This will need to be adjusted based upon your actual vehicle but is a reasonably accurate estimate of ET for most folks who are "bench racing".

Back in my first season of racing, in 1998 my car ran a best of 8.75 in the 1/8 and had a 1/4 mile time of 13.61..... The 1.55 conversion says it would have run 13.56. My car always had a better 1/8 than it should have for the 1/4 mile time, probably becasue it was always low on the mph. basically may car's ET's were better than the mph should have allowed. Everybody's cars run different.

[jking]

Another example was my Mach 1 vs. my C5.

My C5 ran a best stock time of 12.89 @ 110.89, and turned an 8.44 in the 1/8. 2.03 60'

My Mach 1, stock on full psi DR's ran a 12.90 @ 106 with an 8.27 in the 1/8. 1.87 60'.

Nearly identical 1/4 times, but you can obviously see from the numbers how each car got there.

[grandkodiak]

gotcha... thanks for the input