1956-1962 Corvette Alignment Shim Front Aluminum This aluminum shim was found on all 56-62 cars, but can also be put on 53-55 cars. The addition of the tapered shim increases front wheel caster. Thickest part of shim goes toward rear of the car. To tilt the top of the suspension crossmember rearward, increasing the nominal positive caster angle and providing more range of positive caster adjustment, the tapered aluminum shim was added between the bottom of the frame and the top of the crossmember. This improved high-speed straight-ahead tracking and steering returnability at all speeds, and entered production at approximately 1956 VIN#4000 along with a modified steering third arm support bracket.
Wow. What a crappy die cast part. I would hope the application doesn't a require a non-porous part! - EM