Saturday, January 5, 2013

Anti-Roll Bars for the GT40

Adjustable blade type sway bars are a lot of fun to construct. Problem as always on a GT40 was space. I purchased the blades, bars and fixed arms from Genesis Technologies Race Car Parts and Equipment. Pillow blocks for the bars were sourced elsewhere and are alloy with self centering bushes fitted in them, very nice units.
REAR
When the transaxle mount was designed clearance was left between the mount and the transaxle for a roll bar. Modifications to the shock uprights were also made to accommodate the sway bar bearing mounts.
The roll bar was cut and welded to the adjustable bush on the right (below). On the left a standard fixed arm was modified to angle outward.
The sway bars are hollow and 25mm in diameter. At the end of the "blade" arm (above) are bearings in the supporting tube that allow the blade to rotate and adjust the sway bar stiffness. These are pretty common units in race applications. I used a spline on the end where the bar connects to the rigid arm so the removal of the assembly is easy. The rigid arm was milled and bolted to bend it rather than heating it up etc. The end result is very strong and exact.
Drop links were turned up on the lathe and groves added on the mill.
FRONT
The front bar was routed through the chassis to keep the space ahead of the foot area clear. The self centering bearings ensured the bar does not bind due to it being impossible to get both sides of the alloy chassis parallel. Missing the brake cooling duct in all suspension & steering lock combinations was tricky.
The completed bar setup fits really well and will provide ample adjustment potential.