63 and 64 rear frame gussets

[Lawrence Parisotto]

I'm restoring a late 64 roadster (build date June 29, 1964) with an original replacment frame that is, as far as I can tell by the numbers, a February 64 frame. However, this frame does not have the triangular gussets in the frame at the rear just before the rear kick up. My frame diagrams from the 63 Assembly Manual and 64 Supplement do not show these gussets for either the 63 or 64, and Noland Adams does not indicate them in the 63 and 64.

However, I see in Corvette Central and Corvette America catalogues that repalcement rear frame gussets are listed for 64. Question: Should a late 64 frame have these gussets or did they not appear till the 65 model year in September, 1964? Do the gussets add any significant strength?

Thanks in advance,
LP

[Jack J.]

Re: 63 and 64 rear frame gussets

Lawrence, I have 2 good examples of 1964 frames, with and without gussets. My original frame(build date-May1,1964) has gussets. The used frame that I purchased for my body-off restoration has a build date of Nov. 11,1963 has NO gussets. When did GM decide to add the gussets? Perhaps others can chime in so that we can narrow the time down to the month when the gussets were deemed necessary during the 1964 model run.

[Lawrence Parisotto]

Re: 63 and 64 rear frame gussets

Thanks Jack - I suspected that late 64 build cars had the gussets, but wasn't sure; your example supports this. As you suggested, hopefully other responses can narrow it done to month or approximate VIN.
Lawrence

[Stephen W.]

Re: 63 and 64 rear frame gussets

April build date with 115241 VIN , No gussets Original frame

[Jack J.]

Re: 63 and 64 rear frame gussets

Thanks Steve. With your April 9 build date and 115241 VIN, gussets were added within the next 3 week time frame and 1672 cars to my 116913 VIN.

[Stephen W.]

Re: 63 and 64 rear frame gussets

Glad I could help. You hit the date that is on the trim tag to.

[Lawrence Parisotto]

Re: 63 and 64 rear frame gussets

I think I found the answer to my own question - upon closer inspection Corvette Central lists a 64L Rear Frame Gusset for build dates after April 21, 1964. This seems to make sense given the responses that suggest a late April date for when the gussets were added.

A couple of related questions: do the frames with gussets retain the inboard mounts in the center of the frame that 63 and earlier 64 frames had? And, do the frames with gussets have the additional mounting bolts from the floor pan to the gusset?

Thanks again,

Lawrence