Can it be true? Trick handling...
Can it be true? Trick handling suspension pieces for Mopars? The answer is yes, with these tubular control arms from Magnum Force.
Custom handling-oriented suspension components have been a long time coming for Mopar musclecar applications. Over the years, the dedicated enthusiast had little to choose from. Building a custom suspension system meant swapping to up-rated OE parts, modifying components from other applications, or just plain fabrication.
Mopars have traditionally been viewed as straight-line machines, and emphasis on cornering has been outside the mainstream. Be that as it may, some dedicated enthusiasts have long recognized the cornering potential of these machines. In early-'60s compact-car racing, the A-Bodies ruled. Even the '70 Trans Am series showed the potential of the Mopar chassis.
The control arms come with...
The control arms come with RSMX-series spherical rod-ends, which allow a wide range of adjustability compared to a fixed bushing. These rod-ends are manufactured with PTFE liners. Threaded inserts to receive the rod-ends are nicely TIG-welded to the arms' chrome-moly tubing. Magnum Force also produces a similar version of the control arm, which accepts polyurethane bushings instead of the rod-ends.
In comparison to other vehicles of the era, Mopars stacked up well in road-holding ability. Detailed road-test data in magazine evaluations consistently proved Mopars at or near the top of the pack in handling when vehicles from various manufacturers were compared. Even so, technology has moved on in the three decades or so since these machines rolled of the assembly lines, and in order to maintain handling, upgrades are necessary.
Sticky tires, up-rated springs, bushings and sway bars, and a lowered stance is pretty much the formula for a hot-handling Mopar. A potential pitfall is once it's all said and done, lowered, fat-tired Mopars may not have the adjustability in the front suspension to set the alignment to the appropriate specs. The adjustment point for the caster and camber angles is at the inner pivots of the upper control arms, and there is a limited range of travel available there. With a lowered ride height, the factory adjustment is often not enough to obtain the stock settings required for acceptable tire wear, much less aggressive handling. When a Mopar is lowered, the camber angle goes negative. Once the adjusters are set for the static camber specs-if it will even get there-the range of adjustment required to set the caster is lost. Without sufficient caster, high-speed stability is gone. Even with a stock ride height, similar problems can crop up from the chassis settling from years of service.
At the other end, a machined...
At the other end, a machined ball-joint receiver accepts a standard Mopar ball joint, which is pre-assembled to the arm.
There are several potential fixes, including Moog's special offset "problem-solver" bushings, which help some. But, the guys at Magnum Force Racing go one better with a tubular upper control arm designed with performance handling in mind.
Magnum Force Racing markets two basic versions of their DOM seamless-tube A-arms: One is a low-deflection polyurethane bushed unit; the other, the Mac-daddy, is adjustable with spherical rod-ends. Both feature a revised ball-joint position, moving it further out and back. This is exactly where it needs to be to allow for a performance suspension setting. The tubular construction makes for a structure that is more rigid than the stock stamped-steel control arm, and it certainly looks racier. The eye at the bushing end of the bushed version has greater surface area supporting the bushing. This is an area where stock control arms often crack. The Magnum Force control arms come fully assembled with new ball joints and bushings (or rod-ends) and are ready to bolt in.
Our '71 Charger R/T has been previously set up for performance street handling, and we decided to use this vehicle as a test bed for the installation of a set of Magnum Force upper control arms. We opted for the adjustable rod-end-style arms, which offer full adjustability at the control arm as well as the stock adjustment cam, with near-zero deflection. The Magnum Force arms were a simple upgrade and lent a trick custom-performance look to our front suspension.
 Weighing in at 4 pounds, 8...  Weighing in at 4 pounds, 8 ounces with hardware, the Magnum Force arms offer only a 10-ounce weight advantage over the stock arms. |  The rod-end-style arms pivot...  The rod-end-style arms pivot on the stock adjustment bolts and use machined aluminum spacers to match the stock bushing width. The small tapered end of the spacers bears against the rod-end. |  The arms come in bare, unpainted...  The arms come in bare, unpainted steel. We masked the ball joint and shot ours in Hemi Orange urethane for a flashy look. |
 Our control arms are going...  Our control arms are going into a '71 Charger R/T. To prep for the new arms, measure the distance between the lower control-arm bumpstop and the frame with the car sitting at normal ride height. This will provide a reference for later ballpark settings. Jack up the car and support it with jackstands by the framerails, allowing the suspension to drop. Remove the brake calipers to get the brake line clear of the upper ball-joint stud. |  Fully unwind the torsion-bar...  Fully unwind the torsion-bar adjustment screw to unload the torsion bar. |  To separate the ball joint,...  To separate the ball joint, first remove the cotter pin and nut. A pickle fork and hammer can be used, but it will destroy the seal and possibly damage the ball joint. Since this one was practically new, we used a ball-joint separator with a short screw to break it loose without damage. |