C3 frame question
Thread Starter
Intermediate
Joined: Mar 2009
Posts: 25
Likes: 0
From: Draper Utah
C3 frame question
Are all the C3 auto trans frames similar enough that they can interchange? I'll be doing a frame off on my 71 454 auto car starting next fall. I'm collecting parts now. My current frame seems pretty rusty in the rear, past the rear axel. There is a local guy selling a perfect, rust free 76 frame for rear cheap, like $400. Just want to know if it will work in my 71.
Team Owner
Joined: Sep 2006
Posts: 31,172
Likes: 4,250
From: Westminster Maryland
I believe there are many differences but the most obvious would be that the front and rear of the frames differ depending on whether the frame was for a chrome bumper or a later rubber bumper car. So I'd say you should be looking for a 73 or older frame.
Regards,
Alan
Regards,
Alan
Burning Brakes
Joined: Jan 2009
Posts: 1,224
Likes: 1
From: Clarksville Indiana
I got issues with my frame so NO they not the same! I dont know what year 4-speed frame the previous owner stuck under it but the ends of the frame are giving me grief with radiator install.. most issues can be worked around most likely but watch out. theres a lot of frame repair info in here IF you can find it..
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
Drifting
Joined: Jan 2006
Posts: 1,832
Likes: 36
From: Cedar,BC
It will work,but it must be modified.You will have to change out the rear 18" or so of the 76 frame to make it work with your 71,and may have to relocate a hole or two at the front for the brackets.
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
in 73. Might be true but I wonder why the parts book shows the same frame 69-73?
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Melting Slicks
Joined: Oct 2002
Posts: 2,865
Likes: 1
From: I may be getting old but I refuse to grow up
The 74 is a 1 year only frame, if you check the chassis diagrams the body mount heigt changed in 73 and the 1 year only 5 mph bumper slider brakets for 74. not sure how much changed on the front in 73 for the rubber bumper
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
Rick B.
Melting Slicks
Joined: Aug 2006
Posts: 3,429
Likes: 20
From: Kingston Ontario
As mentioned the 76 frame will need a 68 to early 74 rear 18 inches or so and probably the front frame horn bolt holes modified also. The 74 year came with the 68 to 73 rear crossmember in the early part I believe and the later had the boxed rear section. Most tranny crossmembers allow the 4-sp tranny and shifter mount to be bolted on. Also the mounts as mentioned were lowered a bit. Correct me if I'm wrong.
Rob
Rob
Burning Brakes
Joined: Jan 2009
Posts: 1,224
Likes: 1
From: Clarksville Indiana
why dont you get some pics of your rust issues on here and see what these guys in here say about saving your original frame. I wish I had had the chance to decide on the old frame on my car before the previous owner stuck this other frame in there and left the issues for the next guy, ME! lol I have to drill some holes for the outer bumper supports and also do some cutting on the ends of the frame and hope the radiator/shroud will clear then. Thats what I have found SO FAR. Some rust repair of equal effort may be worth it to keep the frame original. Good luck with the project! Heres a good link... http://corvette-restoration.com/
