Motorsports' Clutch-Release System - No Pain, All Gain

Got a tired left leg? Blame the Mustang's ancestry. Your late-model Mustang inherited its clutch cable from the Pinto-based Mustang II.

Sure, the cable was perfectly adequate for working the clutch behind the anemic V-8 of the time, but the Ford engineers probably didn't anticipate that their clutch-release system would still be used 30 years later on a 390hp Mustang Cobra. In fact, it wasn't until the '05 S197 platform that the Mustang got its first hydraulic clutch.

Don't get us wrong--a clutch cable system is simple to design, inexpensive to build, and easy to maintain. When neglected, cable-actuated clutches can become hard to push, especially in high-torque applications. Take the '03-'04 Mustang Cobra, for instance. The Terminator's 11-inch single-plate clutch is designed to hold the supercharged engine's generous grunt, but consequently it takes generous grunt to disengage. In terms of pedal effort, the Terminator probably tops the list. But this also makes it an ideal car to use when investigating how to get the most out of a cable-actuated clutch-release system.

The Maximum Motorsports clutch-release... 

   

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The Maximum Motorsports clutch-release package includes a billet-aluminum clutch quadrant, firewall adjuster, and modified OEM Ford clutch cable.

The subject of this project is an '03 Cobra that already has an aftermarket quadrant and adjustable cable. Even with these parts installed, the owner complained of a "heavy and mushy" clutch pedal that, although adjusted correctly, didn't disengage until pushed completely to the floor.

After extensive research, the owner settled upon a new clutch cable, quadrant, and firewall adjuster package from Maximum Motorsports. As with most of its products, Maximum Motorsports evaluated each component in the clutch-release system to minimize its shortcomings and improve upon the OEM and aftermarket offerings. The Maximum Motorsports package includes a billet-aluminum clutch quadrant, a firewall adjuster, and a modified OEM Ford clutch cable.

Since the two biggest factors that contribute to excessive pedal effort and mushiness are friction and flex, they are the design focus of the Maximum Motorsports clutch-release system. Friction is minimized by utilizing an OEM Ford cable; its stiff cable housing also reduces flex. The Maximum Motorsports firewall adjuster eliminates the need for the rubber bushing on the firewall end of the cable, and the one-piece quadrant further reduces flex.

By an unscientific seat-of-the-pants measurement, the Maximum Motorsports clutch cable/quadrant/firewall adjuster package reduces pedal effort by quite a bit. In addition, the clutch disengages roughly midway through the travel of the pedal, making this '03 Cobra easier and more pleasurable to drive.

Follow along as we highlight the details and installation of the Maximum Motorsports clutch cable, quadrant, and firewall adjuster package.

First we got the front end...        read full caption First we got the front end of the car in the air. A set of ramps would be sufficient, but we used jackstands to get more working room for photos and used the ramps as backup.	If this Cobra had a stock...        read full caption If this Cobra had a stock clutch quadrant, the next step would be to remove it. But since the Cobra has an aftermarket quadrant and adjustable cable, we began at the clutch-fork end of the cable by removing the 8mm screw and the clutch cover.	To remove the adjustment and...        read full caption To remove the adjustment and jam nuts from our adjustable aftermarket clutch cable, we used a -inch-deep socket and -inch wrench.
	To disengage the other end...        read full caption To disengage the other end of the cable from the quadrant, we removed the cable from the fork and pushed it into the housing a few inches.	Next we used a large screwdriver...        read full caption Next we used a large screwdriver to remove the clip that retains the clutch cable to the bellhousing.
We then pulled the clutch...        read full caption We then pulled the clutch cable free of the housing.	The cable was attached to...        read full caption The cable was attached to the car in two more spots: at the firewall and on the inner framerail. We used 5mm and 8mm sockets to remove the two screws.	With the cable free, we snaked...        read full caption With the cable free, we snaked it out of the car, noting how the old cable was routed so we could route the new one the same.