Over the previous months, we have highlighted the basic concepts of swapping a Hot Rod Three-Valve crate engine from Ford Racing Performance Parts into a Fox-body Mustang. Until this point, what we've covered has been fairly nonspecific in regards to the car's usage, but that's about to change.
Throughout the early stages of the build, we have gone back and forth about the direction our '88 LX should take. There is no doubt that taking the handling route would equate to loads of on-track fun, but we knew whatever direction it took, it had to be street-friendly. With Bradenton Motorsports Park located close to MM&FF Command Central (about 45 minutes), weekly trips to the dragstrip are an easy way to get our speed fix. This also helped us decide to take the street/strip direction with our modular swap project.
The Fox chassis has always been able to hold its own on the quarter-mile. The factory triangulated four-link rear suspension has no problem planting the rear hides when power is applied. Swap out a few of the factory components (stamped-steel control arms, shocks, and so on) and you can have a serious 60-foot machine. When we started planning the rear suspension of our '88 LX, we took an overall look at the project for direction. For MM&FF, a Three-Valve-powered Fox is outside the norm, so we decided to think outside the box for our rear suspension as well.
Our '93 Cobra clone was originally...
Our '93 Cobra clone was originally modified in the late '90s. Although the solid upper and lower control arms and Koni shocks work well, the bushings are wasted and the suspension is ready for some serious upgrades.
Maximum Motorsports is no stranger to high-end suspension components. The San Luis Obispo, California-based company has been producing suspension products to improve the handling characteristics of the Mustang since 1992. Its success on track has lead to product lines for street-performance, full-blown road-race applications, and now the drag-race market. Maximum Motorsports' new and slightly non-traditional look at straight-line performance played right into the outside-the-box thinking we've applied to the rest of this build.
Once we talked the crew at Maximum Motorsports about our newest build, they were very excited to jump onboard. We were supplied with one of the company's Launch Boxes for the hard-top Fox-body Mustang. The kit included the tubular K-member, A-arms, and coilovers, which were installed in "Modular Makeover" (Jan. '11). For the rear suspension, Maximum sent us one of its heavy-duty torque arm assemblies, as well as a set of full-length subframe connectors, adjustable lower control arms, three-piece adjustable rear sway bar, and Panhard bar assembly. The rear suspension was finished off with a set of H&R progressive-rate rear springs, and Tokico D-Spec adjustable shocks.
The installation was intense-each component could essentially be its own story. We are going to highlight the important parts of each component here, but check out www.musclemustangfastfords.com for loads of installation photos and more information on Maximum Motorsports' Launch Box. And don't forget to check back in a month or two for a full on-track test of this project Fox.
The old suspension is just...
The old suspension is just that-old technology. The solid, non-adjustable lower control arms and the lowered control arm mounts set the rear suspension geometry, and don't allow for any adjustments to improve performance.
The previous suspension design...
The previous suspension design utilized the stock triangulated four-link. Although this system does work, we are ditching the upper control arms in favor of a torque arm from Maximum Motorsports.
The new rear suspension is...
The new rear suspension is a complete departure from the design and style of the components they are replacing. The torque arm eliminates axle-housing rotation under acceleration and braking, which transfers all of the energy to the tires. The Panhard bar locates the axle housing under the car. These components replace the upper control arms, which handle both tasks in the stock triangulated four-link design.
The installation of our rear...
The installation of our rear suspension started with the removal of our old subframe connectors.
Although Maximum Motorsports'...
Although Maximum Motorsports' torque arm will work with other companies' subframe connectors, the system is designed around Maximum's full-length connectors.
Using a couple of pole jacks,...
Using a couple of pole jacks, we raised the frame connectors into position. After verifying that the bars were in the correct location, we welded them using our Lincoln MIG welder.
Once the new subframe connectors...
Once the new subframe connectors were welded in, we moved the car from the four-post lift to the two-post lift for the rest of the installation.
We started by hoisting the...
We started by hoisting the torque arm into position.
It attaches to the rear end...
It attaches to the rear end with four U-bolts that wrap around the axle housing. With the arm in place, we began to measure for the torque-arm crossmember.
The torque arm attaches to...
The torque arm attaches to the crossmember with two polyurethane bushings and a 1/2-inch spacer on a 5/8-inch bolt that threads into the front of the torque arm and is torqued to 220 lb-ft.
This bushing (arrow) is then...
This bushing (arrow) is then lubricated with water-resistant silicone grease and slid into the crossmember.
With the rearend lifted close...
With the rearend lifted close to ride height, and the front of the torque arm jacked up, the crossmember was positioned between the new subframe connectors. Maximum Motorsports supplies tabs, which need to be welded to the frame connectors.
Using the transmission crossmember...
Using the transmission crossmember mount as a reference point, we measured to ensure the torque-arm crossmember was square before welding the tabs with our Lincoln welder.
The tabs were then clamped...
The tabs were then clamped to the subframe connectors...
...so that they don't move...
...so that they don't move while being welded.
The next step is the adjustable...
The next step is the adjustable lower control arms. The spring perches can be raised or lowered with a 1/2-inch ratchet. This allows you to adjust ride height and fine-tune the suspension so the car launches straight at the strip.
With plenty of silicone grease,...
With plenty of silicone grease, the polyurethane bushings slide over the aluminum bushings on the lower control arms.
A generous amount of silicone...
A generous amount of silicone grease is applied to the outside of the bushings...
... before sliding it into...
... before sliding it into the torque box.
With the rear held securely...
With the rear held securely in place by the torque arm and lower control arms, the Panhard bar is the next piece to be installed.
The next piece to be installed...
The next piece to be installed is the driver-side Panhard bar mount, which mounts over the control arm mounting bracket on the rearend. The Panhard bar mount also serves as the mounting bracket for the driver-side shock.
With the help of Associate...
With the help of Associate Editor Marc Christ, the Parnhard chassis mount was raised over the rear framerails and held in place with C-clamps.
Measurements are needed to...
Measurements are needed to ensure the chassis mount and Panhard bar mount are properly aligned. For proper alignment, both mounting points need to be within 1/4-inch of each other. We hung a string and plumb bob off the rearend housing to get our measurements.
Once the chassis mount has...
Once the chassis mount has been held in place and the measurements have been checked, we used a center punch to mark the frame for the holes that need to be drilled. Two holes get drilled in each framerail. Once the 5/8-inch holes are drilled, a plate and two sleeves slide into the holes. These prevent the framerails from compressing when the chassis mount bolts are tightened.
After measuring the depth...
After measuring the depth of each hole, the sleeves were cut to length. Once the sleeve is slid into the holes, the other side of the framerail and mounting bracket is drilled for the bolts to slide through.
Next on the list was Maximum's...
Next on the list was Maximum's three-piece rear sway bar. The bar measures 1-inch in diameter, and has 0.120-inch-thick tubing and splined ends that the billet arms slide onto.
The bar mounts to the rear...
The bar mounts to the rear end with two brackets and U-bolts that hold it to the axle tubes, and to the frame with a second set of brackets. Solid end links with spherical rod ends attach the sway bar to the brackets mounted on the frame.
With all of the suspension...
With all of the suspension components installed, the shocks and springs are the last pieces to go in. Maximum sent us a set of H&R progressive-rate springs. These simply sit on the adjustable jacking plates on the new control arms and sit in the stock upper spring mounts.
Single-adjustable Tokico D-spec...
Single-adjustable Tokico D-spec shocks will control how quickly the weight moves on the street and track.