Rear Suspension Guide - Factory Coil Springs

A recent addition to the CalTracs lineup is the split-mono spring. This is not only lighter than a multileaf spring, but the design also allows the chassis tuner to split the spring rate front to rear. The front section is used to optimize launch and overlaps the back half, which can be a lighter spring section used to establish ride height.

A recent addition to the CalTracs lineup is the split-mono spring. This is not only lighte

As production cars became wider and lower in the '80s, the classic four-link suspension evolved into the torque arm rear suspension most widely used in the third-generation, '82 to '92 Camaros. It is still a coil spring rear suspension, but the upper control arms were replaced with a single long arm that bolts between the nose of the rear axle and the transmission tailshaft. Aftermarket torque arms such as those from BMR, Edelbrock, and Global West strengthen the arm and relocate it to a much stronger transmission crossmember, which then can be tuned (moved) for IC modifications. Because the triangular four-link upper arms are eliminated, a Panhard bar is required to locate the rear axle laterally under the car. Torque arms can be used successfully in drag race applications, but on cars running quicker than 10s, it's rare to find a third-gen Camaro still sporting its factory torque arm.

A fourth variation on the coil spring suspension hit parade is the three-link. As you have probably surmised, this design relies on a single upper control arm mounted on the top of the rear axlehousing. Obviously, a Panhard bar or Watt's link is also necessary to laterally locate the housing. Chevy used this configuration in its '58 to '64 fullsize cars and more recently in '05-and-later Mustangs. The advantage is the rear suspension is allowed to roll laterally with minimal bind, although a potential downside is that it places the entire upper bar tension into one single mount, which may have to be reinforced when applying serious power to the ground.

The most popular factory coil spring rear suspension is the four-link, using splayed upper arms such as in our '66 Chevelle. Several companies offer adjustable upper control arms that allow you to set the pinion angle.
The most popular factory coil spring rear suspension is the four-link, using splayed upper
Lakewood originated the No-Hop bar that relocates the rear upper control arm off the rear axlehousing. This shortens the instant center position (see Suspension Simulation sidebar). One negative to this modification is that it decreases clearance to the floorpan, which makes lowering the car problematic, unless you are willing to perform sheetmetal surgery. As an alternative, the instant center can be shortened by lowering the rear mount of the lower control arm.
Lakewood originated the No-Hop bar that relocates the rear upper control arm off the rear
Dick Miller Racing (DMR) and others sell an adjustable antiroll bar (arrow) that bolts to the rear suspension and controls body twist. This is a great tuning tool that allows you to counteract body roll on acceleration. This system is what delivers that clean launch where both front tires lift evenly on the starting line.
Dick Miller Racing (DMR) and others sell an adjustable antiroll bar (arrow) that bolts to

BMR makes this interesting torque arm conversion for early Camaros and Firebirds that converts the leaf spring suspension into a coil-sprung-torque-arm version using a dedicated crossmember for several different transmissions. The lower control arms bolt into the stock front leaf spring position, and the front pivot is designed to slide fore and aft to prevent binding. The conversion requires a Panhard bar and is designed around either a 12-bolt or a custom 9-inch rear axlehousing.
BMR makes this interesting torque arm conversion for early Camaros and Firebirds that conv
The three-link has returned under late-model Mustangs as seen here under an FR500CJ Ford drag car. The three-link uses parallel lower control arms with a single center-mounted upper control arm mount (arrow 1). This necessitates the use of a Panhard bar (arrow 2), which prevents lateral housing motion.
The three-link has returned under late-model Mustangs as seen here under an FR500CJ Ford d
Late-model Ford Crown Victorias use a parallel four-link rear suspension, relying on a factory Watt's link mounted on the front side of the rear axlehousing. The link's pivot point (arrow) becomes the rear suspension's roll center.
Late-model Ford Crown Victorias use a parallel four-link rear suspension, relying on a fac