Frame Experts, Need Help - '73 vs. '69-'72
#1
Heel & Toe
Thread Starter
Frame Experts, Need Help - '73 vs. '69-'72
My '71 (auto) is in desperate need of a frame swap...or major surgery. I have found two frame options locally, which are:
1) '72 4sp - decent shape; would modify the tranny cross-member; not sure of its past, so would send to frame shop to straighten and prep as required; transfer my susp and run new lines
2) '73 auto - this is full rolling chassis off of a "running" car; body, engine comp, other stuff is hacked, so it is being parted out; frame is in good shape
In searching for details about the differences of the '73, all I have come up with is that the body mounts were dropped for thicker rubber.
I'm hoping somebody out there can help me determine if there were other changes. For example, did the frame horns change for the new front bumper requirements or did that change wait until '74?
Any help is appreciated...
Thanks,
Eric
1) '72 4sp - decent shape; would modify the tranny cross-member; not sure of its past, so would send to frame shop to straighten and prep as required; transfer my susp and run new lines
2) '73 auto - this is full rolling chassis off of a "running" car; body, engine comp, other stuff is hacked, so it is being parted out; frame is in good shape
In searching for details about the differences of the '73, all I have come up with is that the body mounts were dropped for thicker rubber.
I'm hoping somebody out there can help me determine if there were other changes. For example, did the frame horns change for the new front bumper requirements or did that change wait until '74?
Any help is appreciated...
Thanks,
Eric
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#3
Heel & Toe
Thread Starter
Thanks Mike...that's the reference where I learned about the body mounts being lowered in '73.
There was no mention of the front frame horns, so I wasn't sure if it was all inclusive.
I continue to dig through threads for more info on the topic. Rick B. (72LS1Vette) swapped a '72 frame for a '73 and had to tweak the front bumper brackets to line-up with holes in the front frame horns. Not sure if he used the '73 rubber mounts (taller) when dropping the body.
I also found a post that mentions the proportioning valve is located closer to the A-arm in '73.
Still digging...
Eric
There was no mention of the front frame horns, so I wasn't sure if it was all inclusive.
I continue to dig through threads for more info on the topic. Rick B. (72LS1Vette) swapped a '72 frame for a '73 and had to tweak the front bumper brackets to line-up with holes in the front frame horns. Not sure if he used the '73 rubber mounts (taller) when dropping the body.
I also found a post that mentions the proportioning valve is located closer to the A-arm in '73.
Still digging...
Eric
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Thanks Mike...that's the reference where I learned about the body mounts being lowered in '73.
There was no mention of the front frame horns, so I wasn't sure if it was all inclusive.
I continue to dig through threads for more info on the topic. Rick B. (72LS1Vette) swapped a '72 frame for a '73 and had to tweak the front bumper brackets to line-up with holes in the front frame horns. Not sure if he used the '73 rubber mounts (taller) when dropping the body.
I also found a post that mentions the proportioning valve is located closer to the A-arm in '73.
Still digging...
Eric
There was no mention of the front frame horns, so I wasn't sure if it was all inclusive.
I continue to dig through threads for more info on the topic. Rick B. (72LS1Vette) swapped a '72 frame for a '73 and had to tweak the front bumper brackets to line-up with holes in the front frame horns. Not sure if he used the '73 rubber mounts (taller) when dropping the body.
I also found a post that mentions the proportioning valve is located closer to the A-arm in '73.
Still digging...
Eric
IIRC I had to drill one extra hole in the bumper brackets and elongate one other hole to get the bolts in. Unless your car was being scrutinized by a Corvette expert no one will ever notice.
I don't know if the proportioning valve is relocated on the 73 frame. I put in new brake lines and everything lined up correctly.
Rick B.
#6
Heel & Toe
Thread Starter
Thanks Rick!...
BTW, I plan to rig up a chain fall similar to the one you and your sons used to lift the body. You guys did some great work in tight quarters!
-Eric
BTW, I plan to rig up a chain fall similar to the one you and your sons used to lift the body. You guys did some great work in tight quarters!
-Eric