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Old 07-16-18, 06:44PM   #1
Gach
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Default 1/8 mile

What changes do you make for 1/8 mike vs 1/4 mile.

More gear for 1/8 ?

Different convertor ?
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Old 07-16-18, 08:02PM   #2
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Related ?

60 Ft. Times - Interesting read


http://www.truestreetcars.com/forums...ting-read.html


"Those that can't run 1/4 mile seem to love 1/8 mile. Someday we'll be racing 60ft"
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Old 07-16-18, 08:09PM   #3
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And for the 'BIG BOYS'..............

"Our only track is quarter mile, but several years ago, a former track manager held three eighth mile events on the street, in Anchorage. I bought another third member and 5.86 gears (too low) to replace my 4.57s. Well, anyway, I fell in love with the eighth, and have done some research. It was all made simple when in the September 15, 2006 issue of DRM had an article, in Tech Stop, called "MPH in the Quarter vs. the Eighth". Basically it says, for lower horsepower cars (I assume that means under about 2000), divide the gear ratio that you run in the quarter by .80, and it should be real close to the gear that you need for the eighth. For the guys that run the eighth and want to run the quarter, multiply your gear ratio by .80. For the Pro Mod guys, it's probably a whole different ball game."


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Old 07-16-18, 08:49PM   #4
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So 4.30 dividend by .80 = ?
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Old 07-16-18, 09:37PM   #5
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For conversation here, certainly not set in stone ! And heads up or bracket racing ?

If your track changes from 1/4 mile to 1/8 mile only. Then a rear gear change would be in order say most. Maybe a converter change, it depends. Like a change in the converter to allow for a less gear.

Some might suggest the cam.... probably not. You make the 'power' and choose the gear and converter to suit it. That said, maybe a tighter lobe separation might be helpful under some circumstances, like moving the torque to recover on a shift of the transmission.



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Old 07-16-18, 11:04PM   #6
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Steve...That all makes sense basicly no easy solution, hook the computer up and see what it likes. Maybe just a few changes but then again it be like planing from the get go to run 1/8 mile on motor set up. I guess if your bracket Racing probably doesn’t make much difference going from 1/4 to 1/8 mile, but heads up whole different ball game.
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Old 07-16-18, 11:05PM   #7
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I was just curious what it would take to make the change
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Old 07-17-18, 06:12PM   #8
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The staging routine & driver reaction times have to be flawless.
There is less room to play catch up and run an opponent down if you are late.
Bracket racing is affected the same way.

Down time between rounds tightens up because the staging lane/starting line pacing is faster.
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Old 07-24-18, 08:37PM   #9
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Quote:
I don't change anything. I set up to run the 1/4, but mostly run the 1/8th. I could probably go a little faster if I made some changes to run just the 1/8th but I doubt it would make a huge difference so I just set up to run the 1/4 and leave it alone.
Good info, that’s what I was wondering if it made that much of a difference, I guess if your competing heads up it might be worth chasing ET or 60’s
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Old 07-25-18, 02:42AM   #10
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What hell, thought I Quoteing Pro Bird. That’s weird,
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Old 07-25-18, 02:43AM   #11
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Must hit edit instead of Quote...LOL sorry about that
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Old 07-25-18, 10:01PM   #12
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We change rear gear.
4.10 to 3.70 from 1/8th to 1/4
and take less timing out of the launch retard
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Old 07-26-18, 01:04AM   #13
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I figured they’d be a gear change involved.
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Old 07-26-18, 02:26AM   #14
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Thats where having a 9" rear comes in handy. You can have a extra 3rd member sitting in the garage.
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Old 07-27-18, 01:06AM   #15
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Nah, they eat up to much hp. Wink... Would be nice tho to change gears that quick. Was always gear 1/4 mile, but like ProBird says if your bracket Racing ( unless heads up ) doesn’t really make that much difference.
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