C1 Front end Tapered Crossmember Shim

[John Lanning]

Hello,
I am beginning the reassembly of the frame on my 54' and had a question regarding the tapered plates, or shims, that were installed as an improvement on the 55' Corvettes between the frame and front crossmember. It was suggested I install these on my car to improve the handling a bit. Question I have is ... is the thick part of the shim installed to the front of the car or toward the rear?

Thank You!
John Lanning

[Michael L.]

Re: C1 Front end Tapered Crossmember Shim

John, on my '55 the thick part of the shim is towards the rear.

[James F.]

Re: C1 Front end Tapered Crossmember Shim

John, It's your ;54 and you should do as you dsire. To understand the reasoning behind the addition of the shim may be helpful to your direction. The shim allowed the angle of kingpins to be increased several degrees. High speed testing and races like Sebring found this front end angle to add stability at high speed travel (in '56 100 MPH was considered high speed). The shim found it's way into all '57 and later Corvettes. A hand ful of '56racing Corvettes had the shim. Also included to improved high speed handling would be the rear spring angle which was slightly changed due to changes of the rear frame crossmember spring hanger. These changes in concert helped the high speed straight line stability of the racing Corvettes. Regards, Jim