Muscle Mustangs & Fast Fords
Suspension Upgrade - Project Redheaded Step Child Part 5
Project RSC gets maximized with a new suspension, wheels, and tires.
In truth, I was less concerned about saving a few extra pounds than having the strength required to take the new suspension loads. Back in my road racing days, I experimented with a lightweight tubular K-member on our World Challenge car, only to find out that while it may have been OK for drag racing, the flimsy unit required extensive structural surgery before it could withstand the punishment of road racing. The Maximum piece is ready to go road racing without mods.
It was equally important that the MM piece offered both an increase in wheelbase of 3/4 inch (thereby improving the weight distribution) and optimized vertical location of the control arm pivot points. The ideal mounting location (and therefore angle of the control arms relative to the ground) changes with the desired ride height. Dual pickup points on the K-member provide alternate mounting locations to keep the arms parallel to the ground, offering both an improved camber curve and roll center height.
Unlike many of the aftermarket tubular control arms available, the pair from Maximum Motorsports were a true A-arm design, offering a brace between the V shape produced by the pair of tubes converging from the pickup points to the ball joint. This cross brace adds a great deal of strength to the design, minimizing deflection. Like the tubular K-member, the control arms offer significant weight savings, in this case, over 13 pounds. Though MM offers offset control arms that provide an increase in wheelbase of 3/4 inch (making a total of 1 1/2 inches when combined with the K-member), we opted once again for the more street-oriented standard offset arms.
When combining the offset arms with the K-member, it is sometimes necessary to modify the fenderwell to accept the forward position of the wheel/tire package. Not wanting to modify the fender lip, we chose the standard arms.
The tubular control arms required the use of coilovers, so MM supplied its front system consisting of Bilstein struts (with sport valving) combined with 375-pound coil springs. For race applications, spring rates over 400 pounds might be applied along with race valving in the struts, but once again, this street application requires appropriate spring rates and shock valving.
Other modifications to the front suspension included new urethane mount bushings and endlinks for the factory front swaybar, a set of aluminum steering rack bushings, and adjustable tie-rod ends. The urethane mount bushings and endlinks improved the response rate of the factory tubular front swaybar, while the aluminum steering-rack bushings eliminated any bushing deflection to greatly improve steering response.
The real change to the steering came from the adjustable tie-rod ends, which allowed us to adjust the bumpsteer (changes in toe as the suspension moves up and down). Changes in the amount of bumpsteer present were made by altering the number of spacers between the tie-rod end and the spindle. Once dialed in, the bumpsteer was minimized to just 0.020 per inch of suspension travel-pretty good for a strut front suspension. Nice touches on the adjustable endlinks included the machining of a hex at the inboard end (to facilitate adjustment), a wide assortment of high-alloy steel spacers, and two pairs of different length bolts to ensure proper fitment of the necessary spacer arrangement. It was necessary to drill out both spindles to accept the through bolt, but MM also offers adjustable tie-rod kits to work with the stock (tapered stud) spindle, though this combination is limited to moderate changes in geometry.