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Author Topic:   5th arm distance?
racer2b
Dirt Roller

Total posts: 10
posted April 11, 2000 11:32 AM  
Where do you measure to get the 5th arm 34 to 36 inches out? Also does anybody see any problems with running:
500# w/ 7500 lf
550# w/ 7600 rf
200# w/ 9500 lr
225# w/ 9500 rr
400# w/ 7300 5th
52.5% left
54% rear
120#s heavy lr
This brings the cross up to about 52.5%-any problems with this. Oh the car is a 4-bar wide Masters. Feel free to add comments/suggestions. Thanks in advance.

Roll Steer
Dirt Roller

Total posts: 14
posted April 11, 2000 12:05 PM  
Measure from the centerline of the rear axle to the point where the shock/spring mount on the 5th arm. The torque created by the rear end "rotates" around the centerline of the rear axle.

Your setup looks good as a general starting point. You can work from there depending on the track size and driving style. Good luck.

racer2b
Dirt Roller

Total posts: 10
posted April 11, 2000 02:04 PM  
Rollsteer-so you're saying the center of the tube to the shock mount?

Roll Steer
Dirt Roller

Total posts: 14
posted April 12, 2000 07:09 AM  
Yeah, the center of the axle tube to the shock mount is the correct measurement. You may want to have two crew members hold a string from the LR to the RR directly below the axle tube so that you won't have to guess where the centerline passes through the rear end housing.

One more thing....When you mount the shock make sure the top of the shock is leaning slightly forward if you don't have one of the angle adjustable fifth arms. The shock mount on the fifth arm will move forward a little on the solid fifth arms as the pinion rotates up. Hope this helps!

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