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1/8 mile vs 1/4 mile

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Old May 21, 2008 | 08:37 PM
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REJ
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1/8 mile vs 1/4 mile

Just found out that the local track only does 1/8 mile drags for insurance reasons.

If I was building a car to run 11's in the 1/4, what would I need to do different for the 1/8?
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Old May 21, 2008 | 08:40 PM
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Car: 91camaro rs,2014 silverado 5.3L
Engine: 5.7Lcarb,5.3L
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Re: 1/8 mile vs 1/4 mile

the gearing will mostly likely be different
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Old May 21, 2008 | 08:53 PM
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Car: 1984 Trans Am
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Re: 1/8 mile vs 1/4 mile

well if its strictly a drag car, then gear it to top out at the 1/8th instead of the 1/4.. mph will be anywhere from 88-97mph for an 11sec car.. 88 being 11.99 and 97 being 11.00..

your gear ratio should be 5.xx..
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Old May 21, 2008 | 10:24 PM
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
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Re: 1/8 mile vs 1/4 mile

Trouble with that is that you can have too much gear and overpower the tires off the start line.

Under normal conditions and setup, a drag car should be set up so that you go into high gear (not OD) at or just before the 1/8 mile mark. All the shifting is done in the first 1/8 mile and the last 1/8 mile is a high gear, brute HP pull to the finish. If you had too deep a gear, you would probably be shifting out of first by the 60' mark.

Based on that idea, you set it up to run a 1/4 mile where it's topped out as you cross the finish and just run 1/8 mile instead. As soon as you shift into high gear, the race is over.
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Old May 24, 2008 | 01:18 AM
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Engine: Built 383, Vortech SC
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Re: 1/8 mile vs 1/4 mile

Stephen, Excellent! I race 1/8th mile. I cross the finish line in second gear at 6000 rpm, shift into 3rd and slow down. 700R4, 3.54s, 26in tire, 2800 stall. Street car, driven to the track, high 7.70s at 93. Works for me.
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