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View Full Version : Swing arm set-up help



Dirt Knife
01-07-2013, 09:58 AM
With a swing arm car you run heavy er springs because of the motion ratio created by the swing arm. 425/375 vs. say a 200 225

Do you run heavier shock valving also?? where you would run a 6/4 instead of a 5/3

With pull bar spring heavier also??

Thanks for any input

JustAddDirt
01-07-2013, 01:24 PM
Depends on were you run the shock. If you run a coil over shock and mount it on the swingarm, yes. Compression and rebound need to be compensated for due to motion ratio.

If you run the shock off the backside of the birdcage, then no.
i would start the pullbar off at a 600-2000 progressive. similar to a floated 4-link car.
Long pullbar, left of driveshaft.

Dirt Knife
01-07-2013, 01:37 PM
Yes run the coil over on the swing arm Thanks

Towers21
01-17-2013, 08:41 PM
When the coil over mounts to the swing arm does it kick it to the outside, ie. does it have a heim on each end and twist the heims and force the swing arm to the outside from the angle at the top of the coilover? I had a swing arm RR and it had a floating spring perch, so no coilover, and it didnt float it just bent the spring up all crazy. Took that off and made a mount on the swing arm to bolt the coilover to it and with heim on each end of course it kicked it to the outside. Thought of using a solid heim but this would bind up with all the roll steer. Just curious about your mounting setup.

HEAVY DUTY
01-18-2013, 08:37 AM
When the coil over mounts to the swing arm does it kick it to the outside, ie. does it have a heim on each end and twist the heims and force the swing arm to the outside from the angle at the top of the coilover? I had a swing arm RR and it had a floating spring perch, so no coilover, and it didnt float it just bent the spring up all crazy. Took that off and made a mount on the swing arm to bolt the coilover to it and with heim on each end of course it kicked it to the outside. Thought of using a solid heim but this would bind up with all the roll steer. Just curious about your mounting setup.
Most people try to run too soft of a spring on a swing arm. This is what causes the spring to bow.The spring mount on the swingarm has to be below the line drawn thru the hiems on the ends of the arm. Without a coil over, the spring has to hold itself straight, and if it is too soft, the spring cant hold itself straight. What length of swingarm do you have? and what spring rate?