need help with frame horn alignment
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
need help with frame horn alignment
I asked this before but didn't get an answer - I have to believe someone else has had this issue.
I am putting my 72 back together with a different frame. When I go to bolt the frame horns on only 2 1/2 of the 4 bolt holes line up. I can make different ones line up and for now have chosen to use the two with the nuts welded to the frame. I have looked at several frame history pages and none of them mention this changing.
I am going to put the body back on next week and can do a trial and error but thought someone here may have done it before and know the right way.
I am putting my 72 back together with a different frame. When I go to bolt the frame horns on only 2 1/2 of the 4 bolt holes line up. I can make different ones line up and for now have chosen to use the two with the nuts welded to the frame. I have looked at several frame history pages and none of them mention this changing.
I am going to put the body back on next week and can do a trial and error but thought someone here may have done it before and know the right way.
Racer
Joined: Apr 2007
Posts: 492
Likes: 3
From: Temecula CA
I assume it is a 72 frame. When I did my front clip, the holes lined up. Maybe there are mid-production run differences and I just got lucky??? If you don't want to drill new holes, I'm sure the two bolts will be adequate, given their stout size.
temvette72
temvette72
Burning Brakes
Joined: Sep 2005
Posts: 895
Likes: 4
From: whitman massachusetts
alignment
First off, let me make sure you understand that my input is that of a rookie, so take it for what its worth. My guess is that the frame you are putting back together is actually a 1973. I believe you can verify this by numbers on frame, if they are not legible, than you can measure the body mount tabs on frame. I believe the 1973 frames mounts were a little lower than previous mount heights, to accomodate the rubber type mounting bushings that were introduced in 1973. This will be an issue you would want to address before you try to remount your body in order to avoid the hammer through the windshield problem that would come next
If that is the case, I believe you are correct in using the existing backed up nut holes as an alignment aid in drilling out the other two holes in frame for your remaining attachment points. Again, I am not positive about this, but it might save you some anguish lf you check it out now, as opposed to when mounting body. Hope this helps.
If that is the case, I believe you are correct in using the existing backed up nut holes as an alignment aid in drilling out the other two holes in frame for your remaining attachment points. Again, I am not positive about this, but it might save you some anguish lf you check it out now, as opposed to when mounting body. Hope this helps.
Team Owner
Joined: Sep 2006
Posts: 31,212
Likes: 4,300
From: Westminster Maryland
Hi SPF72,
After looking at my 71, I can see the 2 bolts you have installed are in the holes for the bumper brackets. The other 2 holes are for the frame extensions you're trying to put on.
Does that help you get things lined up? Remember, the bumper bracket covers the rear bolt of the extension when you put it on.
Do you know what year frame you have?
Regards,
Alan
I can now see the frame holes are in the wrong place. Since the 2 bolts you have installed anchor the extension in the correct location, I think you can drill the 2 new holes in the frame, put the extention bolts in the right place, then take the 2 bumper bracket bolts out, mount the bracket, and put the bolts back in. This is all based on the premise that the bumper bracket holes and their welded on nuts are in the right place for a 72 frame.
The rear most hole in the frame is for the frame extension and should be about 2 inches straight back from the rear hole and welded on nut for the bumper bracket.
After looking at my 71, I can see the 2 bolts you have installed are in the holes for the bumper brackets. The other 2 holes are for the frame extensions you're trying to put on.
Does that help you get things lined up? Remember, the bumper bracket covers the rear bolt of the extension when you put it on.
Do you know what year frame you have?
Regards,
Alan
I can now see the frame holes are in the wrong place. Since the 2 bolts you have installed anchor the extension in the correct location, I think you can drill the 2 new holes in the frame, put the extention bolts in the right place, then take the 2 bumper bracket bolts out, mount the bracket, and put the bolts back in. This is all based on the premise that the bumper bracket holes and their welded on nuts are in the right place for a 72 frame.
The rear most hole in the frame is for the frame extension and should be about 2 inches straight back from the rear hole and welded on nut for the bumper bracket.
Last edited by Alan 71; Feb 1, 2009 at 12:28 PM.
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Thanks for your input. First a few more "facts" - I do not know what year frame this is, I bought it at Carlisle and had an "expert" with me who assured me it would fit as "they are all the same through 73". The year is one of the things I wanted to find out here if someone knew.
I have checked every other measurement against my 72 frame and they were the same including the body mounts (I will be using 73 and up rubber mounts so it actually would be good if that were the issue)
Every frame place I check including those on this forum FAQ say only the early 68 was different and the late 68 through 72 were the same with minor changes. Clearly that is not the case. One site has a year by year breakdown of all the minor changes and nothing is mentioned about the horns.
The frame horns are off my 72 so I know they are right. For now I think I will be doing as Alan suggested and bolt the bracket bolts and drill the other two. One is very close and the other not so much. I thought I may wait until I fit the body to be sure unless someone absolutely knows.
I have checked every other measurement against my 72 frame and they were the same including the body mounts (I will be using 73 and up rubber mounts so it actually would be good if that were the issue)
Every frame place I check including those on this forum FAQ say only the early 68 was different and the late 68 through 72 were the same with minor changes. Clearly that is not the case. One site has a year by year breakdown of all the minor changes and nothing is mentioned about the horns.
The frame horns are off my 72 so I know they are right. For now I think I will be doing as Alan suggested and bolt the bracket bolts and drill the other two. One is very close and the other not so much. I thought I may wait until I fit the body to be sure unless someone absolutely knows.
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
My guess also is that the new frame is a 73. I had to modify the bumper extensions to fit when I put my 72 body onto the 73 frame. I had to drill 1 new hole in the extension and slot another to get the bolts to line up. I didn't do any mods to the frame horns.
Rick B.
Rick B.
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Le Mans Master
Joined: Jun 2005
Posts: 5,447
Likes: 3
From: Syracuse NY
Thanks for your input. First a few more "facts" - I do not know what year frame this is, I bought it at Carlisle and had an "expert" with me who assured me it would fit as "they are all the same through 73". The year is one of the things I wanted to find out here if someone knew.
I have checked every other measurement against my 72 frame and they were the same including the body mounts (I will be using 73 and up rubber mounts so it actually would be good if that were the issue)
Every frame place I check including those on this forum FAQ say only the early 68 was different and the late 68 through 72 were the same with minor changes. Clearly that is not the case. One site has a year by year breakdown of all the minor changes and nothing is mentioned about the horns.
The frame horns are off my 72 so I know they are right. For now I think I will be doing as Alan suggested and bolt the bracket bolts and drill the other two. One is very close and the other not so much. I thought I may wait until I fit the body to be sure unless someone absolutely knows.
I have checked every other measurement against my 72 frame and they were the same including the body mounts (I will be using 73 and up rubber mounts so it actually would be good if that were the issue)
Every frame place I check including those on this forum FAQ say only the early 68 was different and the late 68 through 72 were the same with minor changes. Clearly that is not the case. One site has a year by year breakdown of all the minor changes and nothing is mentioned about the horns.
The frame horns are off my 72 so I know they are right. For now I think I will be doing as Alan suggested and bolt the bracket bolts and drill the other two. One is very close and the other not so much. I thought I may wait until I fit the body to be sure unless someone absolutely knows.
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
The bumper brackets fit OK. I didn't make any modifications to the frame horn. I figured it is easier to replace a removable braket if I screwed it up than repair the frame horn.
Rick B.
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Thanks everyone. Rick, did you find any other changes in the frame? It's kinda weird they would make this one change in the last year of the chrome front bumper. Makes me wonder why like was it to get ready for the next year? At least that finaly answers the question of what year the frame is, thanks again.
I agree and will just be drilling the bracket - the frame has been a lot of work and I'm not about to risk that!
Steve
I agree and will just be drilling the bracket - the frame has been a lot of work and I'm not about to risk that!
Steve
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
Thanks everyone. Rick, did you find any other changes in the frame? It's kinda weird they would make this one change in the last year of the chrome front bumper. Makes me wonder why like was it to get ready for the next year? At least that finaly answers the question of what year the frame is, thanks again.
I agree and will just be drilling the bracket - the frame has been a lot of work and I'm not about to risk that!
Steve
I agree and will just be drilling the bracket - the frame has been a lot of work and I'm not about to risk that!
Steve
Rick B.
Burning Brakes
Joined: Aug 2004
Posts: 971
Likes: 7
From: roanoke va
Check the rear of the frame very close before the body drop. I would not want to get the body on and find out it's wrong. It would be a pain to repair with the body on or take the body back off.
You may have a 74 frame, the 74 frame that I used to repair mine had two distinct flat spots on the crossmember (the one the rubber snubber go on). The flat spots where one on each side in the ft. where the emg. brake cables run. The 72 did not have these two flat spots. I looked and found this picture of the two spots I am talking about.
Hope this helps, Wilson
You may have a 74 frame, the 74 frame that I used to repair mine had two distinct flat spots on the crossmember (the one the rubber snubber go on). The flat spots where one on each side in the ft. where the emg. brake cables run. The 72 did not have these two flat spots. I looked and found this picture of the two spots I am talking about.
Hope this helps, Wilson
Burning Brakes
Joined: Jan 2009
Posts: 1,224
Likes: 1
From: Clarksville Indiana
Hey while you guys are looking at these pics, I am trying to put mine back together that somebody else took apart. those two frame horns and the connecting V shaped crossmember is where I am stuck. those holes in the frame and frame horns have a lot of slop in them. I mean it can move up and down more than a inch and can be tilted either way a lot also.. since the core support sits on that crossmember and the fenders bolt to the core support.. the whole front clip of the car moves up and down with the slop in the frame/frame horns.... so where is the right spot to tighten them up at? I can jack up the crossmember to take the bow out of the fender wheel well lip and eye ball it but theres got to be a right way to set this and tighten it up? any info from anybody?
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,196
Likes: 47
From: Scarborough Maine Fredericksburg VA
Well at least I now know I have a 73 frame as I do not have the flat spots as pictured on the 74.
As for 71coupe454 question that is an issue I can see happening but I think it would happen no matter what. I looked at my 70 and the brackets are about even with the top of the frame so that is where I was going to start with my 72. There is some slop until you tighten up on the bilts and then it goes away.
Those of you who have gone before us - where did you set your brackets for the initial body bolt up?
As for 71coupe454 question that is an issue I can see happening but I think it would happen no matter what. I looked at my 70 and the brackets are about even with the top of the frame so that is where I was going to start with my 72. There is some slop until you tighten up on the bilts and then it goes away.
Those of you who have gone before us - where did you set your brackets for the initial body bolt up?
Burning Brakes
Joined: Aug 2004
Posts: 971
Likes: 7
From: roanoke va
Here is the way my 72 was before I took it apart. You may want to modify the frame and not the bracket. If I looked at it right one of the bolt heads is very hard to get too once everything is together and the outside bracket my hit the bolt head. It looks like to me by your pictures this hole on your frame is higher than the original hole. The rear hole does not look like it would matter.
Hope this helps, Wilson
Hope this helps, Wilson
