Spohn BS-4 - Manual

Spohn Performance, Inc.
494 E Lincoln Ave Myerstown, PA 17067
1-888-365-6064 www.spohn.net
Part# BS-4 Bump-Steer Kit – 1993-2002 GM F-Body
USE OF THIS PRODUCT IS ACCEPTANCE OF SELLER’S DISCLAIMER OF WARRANTY!
By their very nature, competition components are constantly pushed to their limits. While our components
are designed to withstand intense race conditions, it is impossible to control the quality of installation or
the varying conditions in which they are used. It is for this reason that absolutely no warranty or
guarantee is either written or implied. Neither the seller nor the manufacturer will be liable for any loss,
damage, or injury – direct or indirect – arising from the use of or inability to determine the use of any
product. Before using, the user should determine the suitability of the product for its intended use, and
the user shall assume all responsibility in connection therewith. Spohn Performance, Inc. makes no
guarantee as to the legality for any specific class. Spohn Performance, Inc. makes no claims, nor does it
intend its products to be used in street driven vehicles. Spohn Performance, Inc. reserves the right to
make changes in design or add to or improve on their product without incurring any obligation to install
the same on product previously manufactured. The Buyer agrees to indemnify and hold Spohn
Performance, Inc. harmless from any claim, action or demand arising out of or incident to the Buyer’s
installation or use of products purchased from Spohn Performance, Inc.
INSTRUCTIONS
1. Lift the vehicle and support it with jack stands.
2. Loosen the top nut of the outer tie rod and strike the side of the spindle with
a hammer until the old pin falls out of the spindle (or use a tie-rod puller).
3. Measure and record the distance of the rack end to the center of the outer
tie rod end. This measurement will be used to set the length of the new
assembly.
4. Thread the bump-steer adjuster on to the rack stud and set the center to
center distance as measured in Step #3 above.
5. Insert the tapered end of the tie rod pin in to the spindle and cinch the top
Nylock nut to hold it in place. Torque the top Nylock nut to 45 ft./lbs. and
the bottom locking jam nut to 60 ft./lbs. (See Photo 1 and notes on Page 2).
6. The final choice of the rod end height location will be determined by the
front end alignment shop.
7. Repeat Steps 2-5 on the opposite side of the vehicle.
Notes: Due to the very short length of the 1993-2002 GM F-Body adjusters you may
need to shorten the threads on the rack if you need more adjustment. You may need
to trim some of the thread length off of the bottom of the spindle adapter for proper
wheel clearance depending on what type and size rims you have.
Alignment: Now that you have your Spohn bump-steer kit installed, you will need to
find a front end alignment shop that understands bump-steer, which is essentially a
change in toe-in during suspension travel. To properly perform this alignment, the
technician will put your vehicle on an alignment rack so the front wheels are on
movable tables. He will then likely hook a come-along to the crossmember and one
to the floor that will allow him to pull the vehicle throughout its suspension travel to
measure the change in toe (bump-steer). He will then re-arrange the rod ends
vertical positioning to minimize the problem.
In many cases, a subtle lowering of a car will not be enough to induce bump-steer,
however, severe lowering, or the use of camber-caster plates will often cause the
problem. By changing the angle of the tie rod assembly, done by extending or
lowering the pin height, you can decrease your bump-steer to very small levels (less
than factory).
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