Adjustable VTC-50 antisquat brackets receive the leading end of the upper control arm. They change the geometry in the rear, increasing or decreasing the amount of downforce at the back tires. As part of the package, Global West built specific linear rate coil springs that lower the car 1 inch. Since the engine is all-aluminum, we opted for small-block S-68 at front and S-88 at the rear. Finally, the PHC-50K adjustable Panhard rod that centers and confirms lateral location of the axlehousing, has multihole brackets, and quells rearend instability around turns and over bumps. The relocation rod also imparts a high degree of torsional stability to the framerails.
We had neither space nor the proper telemetry equipment to produce any kind of empirical data, so this is a seat-of-your-jeans take, a report based on driving thousands of new and modified cars. Did it on the street. Did it on an unoccupied thoroughfare with a series of switchbacks, damn difficult to find in Florida. The ride is firm (QA1’s set at three front and rear) but fluid. I can actually feel the front tires through the steering, a facet that was vague at best prior to the changes.
Here’s everything back together...
Here’s everything back together and ready to rock.
Surprise. The Biscayne’s weight distribution is 49/51, undoubtedly a product of its enormous rear overhang, big glass, rear-mount battery, and all-aluminum engine up front that weighs less than an iron small-block. People kill for numbers like this and the car’s handling demeanor is quite neutral. No amount of tomfoolery would call the back end around; although, anything better than a 6/10s effort would probably pendulum the rear of the car easily. Although Global has a rear-mount antisway bar (not attached to the lower control arm) for this conversion, it was deemed unnecessary.
We made some very stupid maneuvers in an effort to upset the cart but got squat in return. Judging by the feel of the car, the bar would be superfluous. The biggest sensation is felt at the rearend. The adjustable Panhard brace and bar really tie the car together. Bumpsteer has been distilled down to nothing. The Biscayne now feels like a modern car, quite the equal of high-zoot, American, Euro, or Asian counterpart. As a matter of fact, BMW dudes despise our big, white junk. It floors them. It brow-beats them. It makes people stay up at night.
The stock antisquat bracket...
The stock antisquat bracket is shown on the right. It is the connection from frame to upper control arm and has no provision for tuning. Brayman replaced it with Global bits, which are adjustable and preclude the need for shims behind them (used to set pinion angle in the stock setup). Excessive squat during acceleration will cause the rear tires to spin. Adjusting the lower control arm down at the rearend will change the percent of antisquat, thus increasing the amount of traction. The antisquat kit will allow you to readjust the angle of the lower arm thereby increasing traction.
The original rear axle assembly...
The original rear axle assembly included Eaton 2-inch drop springs (left). Global’s spring dropped the rear of the car to the same height as did the Eaton coils.
Brayman measured eye to eye...
Brayman measured eye to eye on the upper arm ends and set them as per the length of the old upper control arm. He tightened the brackets with 65 ft-lb of torque. He set the 5/8-inch-diameter connecting hardware at 90 ft-lb.
One side of the Panhard rod...
One side of the Panhard rod attaches to the rearend while the other is joined at the frame. The stock Panhard rod is generally light duty and tends to deflect when the car is driven hard. Raising or lowering the ride height shifts the rearend laterally (no longer in the center of the car) and causes the rearend to be unstable around turns and over bumps, depending on the final angle of the Panhard rod (not parallel to the ground). When the car originally went together, the builder cut the stock rod, threaded either end, and machined a knurled adjuster from aluminum stock. While this is good for centering the axle, optimally the bar should be level with the ground. As you can see here, it isn’t.
Brayman prepped the ends of...
Brayman prepped the ends of the relocation bar and the inside of the framerails with an angle grinder and a sanding disc to remove powdercoating and paint to give the welding rod purchase.
Raising or lowering the car...
Raising or lowering the car requires readjustment of the length in order to center the rear axle under the car. One of the key features of Global’s collection is the track rod relocation kit, which includes an adjustable Panhard rod, a bearing rod end, and a greaseable urethane bushing, all designed to reduce lateral movement of the rear axle in the chassis. The relocation bar (top) also serves to strengthen the frame, and is welded to either side of the inner rails.
|Component Weight (In Pounds) |
| ||OEM ||Global West |
|Upper front control arm: ||9.5 ||9.5 |
|Lower front control arm: ||11.0 ||13.0 |
|Strut bar: ||5.5 ||5.5 |
|Coil spring: ||9.0 ||10.5 |
|Wheel Alignment Specs |
| ||OE ||Global West |
|Caster ||1/4 degree pos. ||Driver side: 4 degrees pos.; pass. side: 4.5 degrees pos. |
|Camber ||1/4 degree pos. ||Driver side: 0.5 degree neg.; pass. side: 0.5 degree neg. |
|Toe-In ||1/8 to 1/4 inch ||0.10 degree pos. |