OFFICIAL 2009 - 2011 SPECIFICATIONS FOR NASCAR SUPER …

(2) The centerline of the rear end pinion must be within one (1) inch of the rear hubs, measured from the left and right hubs where the wheels bolt on. (3) The rear springs must mount on the rear axle in equal distance left to right. (4) Only magnetic steel axles will be allowed. Material other than steel is … ................
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