Frame question - again
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Frame question - again
One of you guys have to seen this! I posted before that only 3 of the 4 bolt holes line up when I put the frame horns from my original 72 frame onto the "new" frame. Well it appears only 2 of the 4 line up! The 2 that line up are the 2 that have the nut welded to the frame and the other 2 are close but no cigar.
If I end up using these 2 and drilling the other 2 how do I know what is leval for the frame horn? Is it supposed to be the same height as the frame? I can't believe I am the only lucky one to have this. Everything else looks fine and the same I just dont want to go through all this and have the front bumper not fit.
If I end up using these 2 and drilling the other 2 how do I know what is leval for the frame horn? Is it supposed to be the same height as the frame? I can't believe I am the only lucky one to have this. Everything else looks fine and the same I just dont want to go through all this and have the front bumper not fit.
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Well - no one seems to know this one, maybe I can sell it as a "rare, one of a kind, only year offerd" 
How about - does anyone know of a place that I can to do research that would know?
How about - does anyone know of a place that I can to do research that would know?
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Thats kinda the question. I bought the frame as a 72 but clearly the frame horns have a different bolt pattern. I am wondering what year frame I have - the body mounts are the same height and all other brackets and the rear crossmember are the same as my 72 - this is the only differnce I can see.
If I can learn the year of the frame maybe I can tell if there are any other differences. If not I need to know if I can either buy different frame horns or drill the ones I have to match the frame. Also, I am assuming that the top of the frame horns should be level with the frame?
If I can learn the year of the frame maybe I can tell if there are any other differences. If not I need to know if I can either buy different frame horns or drill the ones I have to match the frame. Also, I am assuming that the top of the frame horns should be level with the frame?
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Thanks Sunspot for the pics. I will be checking the measurments. I've had over a couple hundred views and no one has seen this before?
My car has a Canadian VIN plate instead of a US plate - is it possible that the front was different? Yes I know this is a stretch but I am coming up blank. I know the front extention changed in 73 but nothing else on this frame has changed.
My car has a Canadian VIN plate instead of a US plate - is it possible that the front was different? Yes I know this is a stretch but I am coming up blank. I know the front extention changed in 73 but nothing else on this frame has changed.
Melting Slicks
Joined: Jun 2005
Posts: 2,293
Likes: 6
From: North of the Bay California
Thanks Sunspot for the pics. I will be checking the measurments. I've had over a couple hundred views and no one has seen this before?
My car has a Canadian VIN plate instead of a US plate - is it possible that the front was different? Yes I know this is a stretch but I am coming up blank. I know the front extention changed in 73 but nothing else on this frame has changed.
My car has a Canadian VIN plate instead of a US plate - is it possible that the front was different? Yes I know this is a stretch but I am coming up blank. I know the front extention changed in 73 but nothing else on this frame has changed.
Steve, can you work around this? Bolt up all the brackets on the front end before you start drilling. I know it will be a pain in the azz with the body on, but after all the brackets are bolted up, maybe you could use an angle drill.
Safety Car
Joined: Aug 2001
Posts: 3,685
Likes: 202
From: Waterford Mi
Can you use the old frame to make a pattern and transfer them over to the new frame? A freind of mine has a car that was suppose to be a 72 but with an 80's still front end. His bolt holes don't line up either but this doesn't help you, just confirms that there are differences.
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Melting Slicks
Joined: Apr 2004
Posts: 2,008
Likes: 38
From: Space Coast Gator Territory
It appears the bolt holes on your frame extension are the same pattern as on my 69. This means the frame hole locations are what is different. Maybe you can use the frame VIN numbers to identify the year frame. Look for them behind the driver side wheel and on top of the frame. I don't think it will make any difference as long as you have the correct frame member on the back. Just drill two extra holes to mount the frame extension. My extension has over-sized, sloppy holes to make adjustments for fit. Just use flat washers to hold the bolts. You can always fill the original frame holes with weld and grind them smooth. This is probably not new information, but my thought on your question.
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Thanks for the feedback - even without a difinitive answer it is good to get suggestions! I have been waiting for someone to say there are other differences that I need to fix - nothing so far.
One of the things that puzzle me is that if it were a 73 then the body mounts would be a little higher and they are not and I believe after (maybe including?) 73 they had a different set up for the rubber bumpers. So that should mean it is between a 68 and a 72 I would think. I have bolted them up and the front "cross member" bolts right up and I should be aboe to adjust the height one I am ready to put the body back on - I think.
I have the old frame sitting right next to it so I put them back on it and took some measurments and pics and by using the 2 holes with the frame nuts it seems to be right. I will now see if I can either buy the different extentions or just oblong the 2 other holes in the bracket to fit. Like I said it does have a Canadian VIN plate but I have always assumed that was because the car had been stolen some time in its past - thats for another thread.
One of the things that puzzle me is that if it were a 73 then the body mounts would be a little higher and they are not and I believe after (maybe including?) 73 they had a different set up for the rubber bumpers. So that should mean it is between a 68 and a 72 I would think. I have bolted them up and the front "cross member" bolts right up and I should be aboe to adjust the height one I am ready to put the body back on - I think.
I have the old frame sitting right next to it so I put them back on it and took some measurments and pics and by using the 2 holes with the frame nuts it seems to be right. I will now see if I can either buy the different extentions or just oblong the 2 other holes in the bracket to fit. Like I said it does have a Canadian VIN plate but I have always assumed that was because the car had been stolen some time in its past - thats for another thread.
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
I could but I thought it may be better to drill the extentions to fit the new frame and leave the frame alone - maybe that is what you meant. I just want to be sure they are put on in the right angle and distance out from the frame!
Burning Brakes
Joined: Sep 2005
Posts: 895
Likes: 4
From: whitman massachusetts
Hole Location
Hey SPF,
Do not know if any of the following will help you out, but here goes. I have a frame off going on a 1971 roadster. It was a basket case with a swiss cheese frame, which I have replaced with a 1973. The hole configuration on the frame horns of the replacement frame(1973) are exactly as pictured in your post. I will be facing the same dilemma that you now have. Why not bolt your existing extensions to your original frame. Once the extensions are torqued to spec on the original frame,take a marker that will show up clearly, and trace the exact frame horn location, onto your brackets. Once completed, remove and attach to your new frame, and see if the horn location is correct. If it is the same, then I would feel pretty confident in drilling the remaining hole in your new frame, using the bracket as your template. I was hoping that you could let me know how things work out, so when I get to this point, I will know how to proceed.
Willem
Do not know if any of the following will help you out, but here goes. I have a frame off going on a 1971 roadster. It was a basket case with a swiss cheese frame, which I have replaced with a 1973. The hole configuration on the frame horns of the replacement frame(1973) are exactly as pictured in your post. I will be facing the same dilemma that you now have. Why not bolt your existing extensions to your original frame. Once the extensions are torqued to spec on the original frame,take a marker that will show up clearly, and trace the exact frame horn location, onto your brackets. Once completed, remove and attach to your new frame, and see if the horn location is correct. If it is the same, then I would feel pretty confident in drilling the remaining hole in your new frame, using the bracket as your template. I was hoping that you could let me know how things work out, so when I get to this point, I will know how to proceed.
Willem
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Willem, that is exactually what I will end up doing and I can post some pics. The frame measures the same so it should work fine - I am hoping anyway.
On your 73 frame are the body mounts also a little (1/4") hogher then the 71? Any other differences? My body mounts are the same and that has thrown me as I thought they went slighty hogher in 73 due to the change in body mounts.
On your 73 frame are the body mounts also a little (1/4") hogher then the 71? Any other differences? My body mounts are the same and that has thrown me as I thought they went slighty hogher in 73 due to the change in body mounts.