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MOPAR ADJUSTABLE BUMP STEER KIT $249.95

Adapts to stock 9/16x18 inner tie rod

Definition of bump steer
Bump steer is a change in toe angle caused by the suspension moving up or down. Bump steer is undesirable because the suspension is steering the car instead of the driver. For a Drag Race vehicle it also scrubs ET and MPH. Changing the ride height or other suspension components can change the way the toe angle responds to the suspension moving up or down. To fix a bump steer problem you need to alter the height of the outer tie rod relative to the steering gear and idler arm [or center link height]. Making big changes requires an adjustable tie rod end that allows you to use washers, or spacers to move the rod end up or down.

Basic Installation
Disconnect and remove the outer tie rod end and adjusting sleeve from the steering arm. Thread a jam nut and new adjusting sleeve, with adaptor, onto original inner tie rod end, [red loc tight adaptor into new adjusting sleeve after test fitting components]. Insert the tapered end of the new spindle stud into the steering arm. Secure it with the supplied nut and washers, torque to 50 ft.lbs.

Adjustment
Set the car on alignment rack or turn tables ,adjust the ride height and adjust toe to zero or 1/16” toe in and document. Next raise the car in 1" increments documenting the ride height and toe angle to full rebound. The goal is to have the smallest possible toe change between at rest and full rebound. Remember, caster angle settings affect bump steer. Increasing caster to the positive lowers the outer tie rod. As more positive caster is added, the less spacer will be needed above the rod end to compensate.

Suspensions

The 1/2 leaf installs on the passenger side spring 2nd from the bottom. It is designed to stiffen the front segment on that side and also to add more bias to control torque roll in the axle. The clamps help tune the spring to launch the car straight and level with no torque steer. In this case we have founnd that the P3412002 and P3412003 mopar SS springs to be the best at controlling spring wrap up and torque roll. These springs are stiffer and .300 thick vs. the standard .250.

Our 1/2 leaf is also .300 thick and has a little arch in it to fit with the rest of the leafs. These springs should be installed with the aluminum front bushings to eliminate deflection in the rubber found in stock bushings. Two clamps should also be installed just behind the passenger front spring eye and one clamp all the way back on the driver's side rear segment. Another good thing to add is an adjustable shock like the 1539 QA1 or Rancho RS9000 (part #99116), as this allows you to adjust for different track conditions and street driving as well. Recommended pinion angle for the street is 4 degrees and 5 to 7 degrees for the track.

Remember that these stock style suspensions tend to overwork the tire, so on good hooking tracks you need to stiffen the shocks and add tire pressure to calm the car down which will lower 60 ft times. Also, just a note about front suspension, when you install SS springs you will notice that there is more arch in the passenger side spring vs. the drivers side this is correct!

It is up to you to now raise the driver's side front with the torsion bar adjuster to lower the pass side rear corner to level the car side to side front and rear keeping a 2 to 3 degree nose down attitude at the sill. This preloads the right rear tire to help control torque roll in the rear axle. For best traction street or strip use a small diameter torsion bar like a 6 cyl or 318 bar and 90/10 front shocks removing the upper control arm stop bumper for maximum front suspension travel.

Last but not least are the alignment angles to use to correct bump steer or toe change due to front suspension travel. After aligning several cars it seems if you can achieve 1 1/2 degrees positive caster and 1/4 degree positive camber it corrects the toe pattern to within an 1/8 inch total toe change throughout the suspension travel. Remember, traction is everything. It is hard to win races spinning or bouncing your tires.

GOOD LUCK!