
The panhard bar bushings have a significant impact on your vehicle's ride, comfort, handling, acceleration, noise and vibration. When the vehicle leans (rolls) in a turn, one side of the chassis moves up relative to the rear axle and the other side moves down. The panhard bar must twist to allow for the axle to articulate, this causes the panhard bar bushings to bind. If this bind becomes excessive, it will raise the rear wheel rate and produce sudden and uncontrolled changes in handling such as snap oversteer.
The factory minimizes this suspension bind by using compliant rubber bushings. These soft bushings help accommodate the necessary motion of the control arms during body roll. However, the rubber bushings do not provide much in the way positive of lateral support.
It is common to replace the stock rubber panhard bar
bushings with polyurethane bushings to resolve the
shortcomings of the factory's soft rubber bushings. The downside
of polyurethane bushings is they prevent the
necessary movement of the panhard bar during body roll, which in turn
produces significant binding in the suspension when the vehicle is
cornering. The polyurethane bushings also place high stresses
on the panhard bar mounts on the vehicle. Polyurethane bushed panhard
bars do not allow for rotation of the panhard bar during cornering
because of the stiffness of the bushings.
Del-Sphere
Pivot Joints:
The Spohn Performance Del-Sphere pivot joint solves the shortcomings of the factory rubber and aftermarket polyurethane bushings. Our Del-Sphere pivot joint incorporates a spherical ball which is surrounded by delrin bushing cups. This combination allows the panhard bar to articulate like a spherical rod end (28 degrees of available rotation) during cornering but the spherical ball does not allow the bushing to deflect. Therefore the panhard bar remains completely bind free like a spherical rod end during cornering for predictable traction in the corners.
Think of the Del-Sphere pivot joint as a Delrin bushed
spherical rod end. After over a year of R&D testing here at
Spohn Performance on a streetable spherical joint the Del-Sphere pivot
joint is the final result. Designed and manufactured exclusively by
Spohn Performance, we have taken street suspension performance to the
next level. Our Del-Sphere pivot joint features a one piece forged and
heat treated chrome moly housing, a heat treated and chrome plated
chrome moly spherical ball, Delrin bushing cups, heat treated retainer
washer and snap ring, heat treated and chrome plated chrome moly
threaded adjuster ring, an external grease fitting and a beautiful
silver zinc plated housing finish. The delrin bushing cups absorb shock
and road noise so you get the quiet and smooth ride of a bushing as
well as 28 degrees of rotation! Our Del-Sphere pivot joints will always
ship to you fully assembled, however, we also offer an optional
adjusting tool that will allow you to do two things. First, you can
disassemble the Del-Sphere pivot joint for cleaning, inspection, etc.
Second, you can adjust the amount of friction on the spherical ball. Do
you want a very low friction pivot joint or a very tight pivot joint?
It's up to you, the amount of tension can be easily adjusted
by using our optional adjustment tool
to tighten or loosen the end retainer ring. What that also means is if
over time and miles the tolerances open up you can simply re-adjust the
retainer ring and have your pivot joint as tight as it was the day it
was brand new. We doubt you'll ever need to replace the Delrin bushing
cups, but they certainly can be. Unlike a spherical rod end,
the Del-Sphere pivot joint is 100% rebuildable.
What
is Delrin, and why
did you choose to use it?
Delrin is an acetal homopolymer made by DuPont. It is
characterized as having an excellent combination of physical properties
that make it suitable for numerous applications. With extremely low
moisture absorption and a low coefficient of friction
(self-lubricating), Delrin is uniquely tailored for wear applications
in high humidity or moisture environments. Delrin will maintain
constant physical properties under high moisture conditions and
out-perform nylon or polyurethane under these conditions. Delrin has a
10,000 psi tensile strength and a 120 Rockwell Hardness rating making
it ideal for our Del-Sphere application.