Motovicity Ticket to Ride – Ford Mustang Build Part 2


The Whiteline front sway bar (part# BFF55Z) is much bigger in diameter with 4-way adjustability.  It also has urethane bushings and strong billet end links.  Billet aluminum clamps will keep the bar from walking back and forth as well.
To make room for the Whiteline Watts the stock rear swaybar must be removed and replaced with a new Whiteline one.  The Whiteline rear bar (part# BFR65Z) is designed to work with the Watts linkage and is thicker and 4-way adjustable to boot.  The Whiteline bar has new axle mounts with urethane bushings and heavy duty billet aluminum, ball and socket joint endlinks that are adjustable so that all preload can be removed from the system.
Whiteline also has a replacement for the upper third link of the rear suspension (part# KTA141A). It is much beefier that the stock upper link which is known to break under hard use. It also has less compliant urethane bushings.  Perhaps the link’s most profound feature is that the chassis side bushing is eccentric which allows some adjustment of the pinion angle and the amount of antisquat in the rear suspension.  The link comes with the bushing in the highest location which is the minimal amount of anti squat.  We feel that this is probably the best for all around use.  Raising the pivot reduces the quickness of the chassis response to torque reaction which is also important.  The third link is very short due to the production car having to have room for a rear seat.  The result of that shortness is that small changes in the angle of the third link make a disproportionately large difference in how the rear suspension reacts to torque load.
A unique feature of the Whiteline suspension system for the Mustang is the use of a Watts linkage for the lateral location of the rear axle (part# KDT916).  For cars that have a 3 link rear suspension an additional linkage must be added to keep the axle from moving from side to side.  The most common way to do this is a Panhard rod which is simply a lateral arm attached to the axle and chassis.  The Panhard rod is effective and simple but has a drawback.  As it swings through its arc, it causes the rear axle to move back and forth from side to side.  This can cause some side scrub and a twitchy feeling at the rear of the car.  The stock suspension uses a somewhat short Panhard rod.  The shorter the rod, the worse the side to side motion will be.  The Watts linkage uses two shorter lateral arms that attach to the axle via a rocker arm.  As the axle goes up and down and articulates the rocker makes up for the difference in arcs between the two links ensuring that the axle will maintain a vertical path.  The rear suspension roll center is determined by the height of the rocker pivot and the Whiteline Watts linkage lowers the rear roll center over stock by having the pivot below the rear axle centerline which will help the car get more off the corner bite.  The kit is a marvelously complicated piece which even requires a new diff cover, but it does its job technically better than simply changing the Pahanrd rod for one with stiffer bushings or moving it on its mounts for a lower roll center.
To install the rocker of the Watts linkage you have to replace the stamped steel rear differential cover with a stiff cast aluminum Whiteline part that has the rocker pivot boss cast in place. Whiteline also incorporated a set of load-bolts into the new differential cover.
The load-bolts help stabilize the differential caps. The load-bolts will help increase overall axle strength by pushing against the bearing caps and reducing deflection under heavy loads.

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