Wes Duenkel
January 4, 2019

Over time, the clutch linkage components on 1979-2004 Mustangs wear out. However, it happens so gradually that the driver usually doesn’t notice until something wears out completely. Once the worn parts are replaced, the difference is often dramatic. If the clutch operation on your Mustang feels sticky, spongy, creaky, or gritty, your clutch cable and its related components need attention.

The clutch linkage on a 1991 Mustang GT was worn from decades of pedal kicks and close encounters with the headers. Rather than just replace the parts with stock components, we contacted Maximum Motorsports for an upgrade. They offer a complete system that replaces the worn parts and also addresses many of the shortcomings of the OEM pieces.

One weak area is the self-adjusting plastic clutch quadrant. Often, it’s either broken or no longer adjusts properly. Maximum Motorsports replaces the plastic assembly with a billet aluminum quadrant and a firewall adjuster that is manually adjustable and more reliable. Maximum Motorsports’ clutch cable is unique to Maximum Motorsports. It’s made in the U.S. by Ford’s supplier, and the quadrant end includes provisions to properly fit inside the Maximum Motorsports firewall adjuster.

Speaking of adjustment, Maximum Motorsports also sent over its Clutch Pedal Height Adjuster, which repositions the clutch pedal so that it’s even with the brake pedal. Like many of Maximum Motorsports’ parts, it’s a simple solution to a common Mustang malady. Maximum Motorsports’ expertise with 1979-2004 Mustangs is not only evident in the parts, but also in the level of detail in its instructions. We rarely run into trouble when we follow the instructions carefully! The following images and captions cover the high points of how the Maximum Motorsports clutch linkage components returned the joy of driving to this 1991 Mustang GT.

Maximum Motorsports’ solution to our 1991 Mustang GT’s clutch woes included its high-quality cable, firewall adjuster, billet aluminum quadrant, and pedal height adjuster.
The Maximum Motorsports firewall adjuster fits 1979-2004 Mustangs and is black hard-anodized to resist corrosion.
The Maximum Motorsports clutch cable features a molded rubber bushing that centers it inside the firewall adjuster. The cable is USA-made by Ford’s cable supplier, so the quality is top-notch.
Maximum Motorsports’ billet aluminum clutch quadrant eliminates the trouble-prone self-adjusting plastic quadrant mechanism.
This bracket and hardware allows adjustment of the clutch pedal’s height so that it’s even with the brake pedal.
We began the upgrade process by removing the driver seat. Do yourself a favor—it only takes a few minutes and makes the installation process much easier.
Using an 18mm socket, we removed the clutch pedal nut.
Then, we pulled the starter interrupt switch retaining pin and removed the pedal.
We first tackled the pedal height adjuster installation. We didn’t have the correct-size transfer punch, but instead we placed a dab of grease in the middle of the supplied bolt.
Then, we positioned the bolt according to the instructions and transferred the grease dab to the clutch pedal.
Using the grease dab as a witness mark, we used a center punch to mark where to drill. Starting with an 1/8-inch drill bit, we enlarged the hole to the final size of 13/32 inch.
Next, we removed the stock clutch quadrant.
Our clutch pedal made a creaking noise, and we noticed the shaft fitment was very sloppy. Go figure: The clutch pedal shaft bushing on the left side was worn, and the right side bushing was missing entirely. We greased and installed fresh clutch pedal bushings on both sides of the clutch pedal shaft.
We installed the Maximum Motorsports clutch pedal height adjuster and clutch pedal shaft, but left the fasteners loose so we could set the pedal height later.
The original clutch cable was burned while getting too cozy with these equal-length shorty headers. Over time, this was bound to cause problems.
We disconnected the cable retaining bracket from the framerail and pulled the cable free from the firewall.
After removing the clutch fork dust cover, we removed the cable retaining clip and pulled the cable from the bellhousing.
Using the supplied hardware, we installed the Maximum Motorsports firewall adjuster, which fits both Fox (one screw) and SN95 (two screws).
Next, we routed the Maximum Motorsports clutch cable in front of the oil filter and connected it to the clutch fork. The Maximum clutch cable is significantly longer than the OEM unit, which helps keep it away from the headers as well as giving it a more generous bend radius.
Before installing the Maximum Motorsports clutch quadrant (right), we compared it to the OEM adjustable contraption (left).
The Maximum Motorsports cable is long enough to cover lots of different bellhousing combinations, but stock setups like ours require installation of the included spacer for the quadrant end of the cable.
With the spacer installed, we threaded the cable through the firewall adjuster.
Next, we hooked the end of the cable on the quadrant, pulled the slack out of the cable, and extended the firewall adjuster until there was about a dime’s width of space between the cable housing and the firewall adjuster.
With the cable tension adjusted, we set the pedal height and tightened the clutch pedal fasteners. Now our clutch operates much more smoothly than before. Success!

Photography by Wes Duenkel