
Application: 1982-2002 GM F-Body
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tour on the bottom of this page.
The control arm bushings on F-Body vehicles 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 control arms must twist to allow for the axle to articulate, this causes the control arm 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 of forward and aft support which can cause wheel hop during hard acceleration and braking.
It is common to replace the stock rubber control arm
bushings
with polyurethane bushings to resolve the shortcomings of the
factory's soft rubber bushings. Polyurethane bushings eliminate wheel
hop, reduce axle deflection, and improve straight line
traction.
However, the downside of polyurethane bushings is
they
prevent the necessary movement of the control arms 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 control arm mounts on the vehicle. Polyurethane bushed
control arms do not allow for rotation of the control arm 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 control arm 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 during acceleration. This provides for great straight line traction like polyurethane bushed control arms but 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.
These combo ended LCAs will still wipe out most
bind, yet keep the road noise increase minimal for
a street driven car. The Del-Sphere pivot joints provide for
"bind-free"
handling performance. The fluted polyurethane bushed ends are mounted
onto the chassis (floor) mount for maximum road noise insulation.
4130N
Upgrade: The
ultimate in bullet-proof lightweight strength,
100% TIG welded 4130N chrome moly construction! Same as above, but
constructed entirely from 4130N chrome moly tubing.
Priced per Pair -- Qty. 1 = 1 Pair