This is what the update is...
This is what the update is all about. The original holes are on the top. The new holes at the bottom are 1-inch lower than the originals. Whether you go with a negative-wedge kit or install the Blue Moon control arms, you'll be supplied with a template to ensure the holes are placed exactly where needed.
One of the more effective modifications Carroll Shelby did to '65 GT350s was relocate the upper control-arm mounting point in the car's shock towers. The result was more cornering power and a decrease in body roll.
As discussed on the Tony Branda Mustang and Shelby Parts Web site (www.cobranda.com), relocating the upper control arms can be done to any '65-'70 Mustang. The relocation, which lowers the upper arm 1 inch in the shock tower, was developed by Ford suspension engineer Klaus Arning. It was originally meant to complement the installation of an independent rear suspension (IRS) system that Ford experimented with for the Mustang in 1964. Shelby got word of the trick and incorporated it into all '65 and some '66 GT350s-through car number 252.
In more recent times, the idea has been taken a step further with the "negative wedge" theory that incorporates a relocation of the upper arm's ball joints. This can be accomplished two ways. One is to install a negative-wedge kit in a car's stock upper control arms. These kits are made by Pro Motorsports Engineering and are available at Marlo's Frame and Alignment. The other option is to install upper control arms that have the ball joint already relocated in the arm. The negative-wedge aspect of the conversion is incorporated into the arm and to correctly install them, the 1-inch lower holes are still drilled in the shock towers, so the geometry is accurate once the arms are installed.
With our '69 Mustang project car, we did the latter in a how-to story in our Nov. '05 issue. There, we installed Control Freak upper and lower control arms, which are made by Blue Moon Motorsports and available from National Parts Depot. At the time, we didn't relocate the upper arms in the shock towers, which in the final analysis, wasn't the best idea. We decided to correct the issue and show you how it's done at the same time.
With that in mind, we headed back to Marlo's Frame and tackled the project, which basically involves removing the upper arms and drilling the 1-inch lower holes in the towers. To make sure everything was correct, we installed another set of Blue Moon Motorsports Control Freak upper arms so the incorrectly stressed ball joints in the first set of arms wouldn't be reused.
Also note that this modification lowers the car's ride height 1 inch in front, which is ideal for better looks and handling. A 1-inch drop doesn't cause drastic ground-clearance issues or remove too much travel from the car's front suspension.
Since our car already has...
Since our car already has the Blue Moon arms, our main task at Marlo's was to remove the upper arms and drill the relocation holes in the shock towers. Though a fairly basic task for a fully equipped suspension shop, it takes a few hours to remove the arms, drill the holes, put it all back together again, and align the front end. We began by removing the tower dust shields, as shown here. One person holds the nuts in place underhood while the bolts are removed from inside the fenderwell.
Blue Moon's Control Freak...
Blue Moon's Control Freak upper control arms (center) incorporate the negative-wedge ball-joint angle into the arm. This means you can drill the holes in the shock tower and install the arms. Also shown is a set of Blue Moon's lower-front control arms. The installation of those was shown in our Nov. '05 issue.
If you retain your car's stock...
If you retain your car's stock upper control arms, they can be relocated. You'll need to install a negative-wedge kit, as shown here. This setup includes new ball joints and hardware, templates to properly locate the holes, and the wedge spacers themselves (center, near top). The spacers install between the ball joints and the arm to keep the ball joint from binding and possibly breaking once the arm is lowered in the shock tower. It also optimizes the camber curve. This kit is made by Pro Motorsports Engineering and is available at Marlo's Frame.
The shocks must be removed....
The shocks must be removed. Unbolt the three nuts at the top of the tower...
...and remove the shock and...
...and remove the shock and its mounting bracket. Two nuts need to be removed on the bottom of the shock where it attaches to the spring perch.
Since our car had shorter-than-stock...
Since our car had shorter-than-stock springs in place, the springs were removed without a compressor. Marlo's compresses the spring by lifting on the lower control arm, then installs these clamps. When the jack is lowered, the clamps keep the spring compressed for safe removal. If your car has stock springs, you'll need a compressor.
With the spring out, remove...
With the spring out, remove the nut that holds the upper arm to the spindle. Note here that the brake caliper and rotor have been removed for easier access to the suspension parts.
A couple of small hits with...
A couple of small hits with a ball-joint spreader shocks the pieces apart, and the arm is easily separated from the spindle.
Next, the arm is removed by...
Next, the arm is removed by unbolting it from the shock tower. A helper needs to hold the nuts in place from underhood while the bolts are turned from inside the fender.
Once the hardware is off,...
Once the hardware is off, the upper arms can be removed from the shock tower.
Both the Blue Moon arms and...
Both the Blue Moon arms and the Pro Motorsports negative-wedge kit come with a template that bolts to the existing holes in the shock tower. The small holes at the bottom serve as pilot holes to begin drilling the new holes, which will make them 1-inch lower than the stock ones. Use the existing hardware from the stock upper control arms, or the new hardware if installing new arms, to secure the template in place.
Place the correct-size bit...
Place the correct-size bit through the holes and drill the pilot holes in the tower. Once they're drilled, remove the template.
Using the pilot holes as a...
Using the pilot holes as a guide, finish drilling the holes in the tower using a bit that will drill the same-size hole as the originals. In the case of the Blue Moon arms, we used a 9/16-inch bit to drill a hole large enough to accommodate the 1/2-inch installation hardware. The finished holes should look similar to those in the first photo.
The arms with the negative-wedge...
The arms with the negative-wedge kit can now be reinstalled. Although our original set of Control Freak upper arms seemed to be OK, we wanted to eliminate the possibility that the ball joints were damaged from not originally relocating those arms. Install the supplied spacer plates with the Blue Moon arms to keep them from hitting the shock tower.
At this point, the task is...
At this point, the task is to put it all back together, which begins with securing the upper arms in place in the new holes.
A knowledgeable suspension...
A knowledgeable suspension shop such as Marlo's Frame has all sorts of time-saving tools and ideas that make suspension jobs such as this easier and faster. This includes using a long bar that provides plenty of safe leverage to hold the arm and spring in place while the arm and spindle are reattached. This can be done with a shorter spring, but with a stock spring, the shop uses a compressor. Once it's back together, the front suspension is compressed with a jack on the lower control arm to allow removal of the spring clamps that are shown in step four.
The upper arms are secured...
The upper arms are secured by reinstalling and tightening the castle nut that keeps the arm and spindle together. Don't forget the cotter pin after the nut is installed.
With everything back together,...
With everything back together, the new ball joints in the upper arms are packed with grease. The job is completed by reinstalling the brake rotor and caliper, then aligning the front end to proper specs for camber, caster, and toe. Good street specs include 1/2-3/4 degree negative camber, 2-3 degrees positive caster, and 1/8-inch toe.