MONTE CARLO Ensuring Frame Alignment

[R.Hodges]

Hello, so I have a 79 Monte that I’m doing a full frame off restoration and has also been sitting for close to 25 years. Before I get too far into the build I want to check my frame measurements.

What is the best way to get the centerline marked in order to measure out from the centerline? I was looking online and found the diagram with all the measurements.

Also once I do find my centerline and let’s say the rear rails are out of whack. Are there any suggestions on how to correct the alignment?

I have all new suspension and rebuilt engine ready to go in. But holding off until I’m sure I won’t have any frame issues.

 

[Northernregal]

Use the alignment holes, behind front drivers body mount and in front of rear most passenger side mount.

 

[R.Hodges]

Use the alignment holes, behind front drivers body mount and in front of rear most passenger side mount.

Sorry if this is a dumb question. But how would I go about checking the frame using the alignment holes? Also here is the dimensions I was referring to.

 

[Texas82GP]

Hello, so I have a 79 Monte that I’m doing a full frame off restoration and has also been sitting for close to 25 years. Before I get too far into the build I want to check my frame measurements.

What is the best way to get the centerline marked in order to measure out from the centerline? I was looking online and found the diagram with all the measurements.

Also once I do find my centerline and let’s say the rear rails are out of whack. Are there any suggestions on how to correct the alignment?

I have all new suspension and rebuilt engine ready to go in. But holding off until I’m sure I won’t have any frame issues.

If you have the frame stripped down, make sure it is really level on your stands or whatever setup you are using. These frames are limp noodles, hence all the bolt in bracing for these cars. Dont believe me? Go push down on the end of the passenger rear frame rail and watch how far the driver's front hikes up off the stands.

 

[R.Hodges]

If you have the frame stripped down, make sure it is really level on your stands or whatever setup you are using. These frames are limp noodles, hence all the bolt in bracing for these cars. Dont believe me? Go push down on the end of the passenger rear frame rail and watch how far the driver's front hikes up off the stands.

Yeah that’s what made the question arise for sure. I went to put the rear bumper on and it was a pretty tight fit. It’s boxed and notched but as far as if it was previously done correctly is unknown. I have read a few post to check using a laser on the center lines of the actual frame. Then measuring from there.

 

[Northernregal]

Sorry if this is a dumb question. But how would I go about checking the frame using the alignment holes? Also here is the dimensions I was referring to. View attachment 181862

Hmmm... not 100% sure about checking the frame, you have the hole measurements on that sheet. I guess I misunderstood the question and assumed you meant alignment of body to frame.

 

[R.Hodges]

Hmmm... not 100% sure about checking the frame, you have the hole measurements on that sheet. I guess I misunderstood the question and assumed you meant alignment of body to frame.

Yeah sorry about the confusion. I have the body off of the frame and the frame is stripped down. Before I dive into painting I just want to be sure its square and all my rails are correct. But really wanted to know if there are any tricks in finding center alignment on the frame.

 

[R.Hodges]

I’m not sure if this will help anyone in the future. But I found a pretty accurate way to check measurements from the center line. Not exactly, but real close since I didn’t have access to a laser.

What I did was took a thick string and tied it to a engine stand and then to the front bumper. I then got the string tight and aligned to the center holes in the frame. Using a paper clip string and a nut tied on the opposite side of the string as the paper clip. I then hung the paper clips with the nuts on the string to get a visual of where I was in accordance with the center holes in the frame.

I then made a few more of my trusty paper clip and nut contraptions and where I was measuring I hung one to make it clear on the tape measure.

There are probably many ways to get the same results but cost wise and what I had on hand it worked well.

I did have a few measurements that were slightly different from one side to the other side of the frame.

Which makes me wonder. Does anyone happen to know what the tolerances were on these frames from the factory?

 

[Hurricane77]

I’m not sure if this will help anyone in the future. But I found a pretty accurate way to check measurements from the center line. Not exactly, but real close since I didn’t have access to a laser.

What I did was took a thick string and tied it to a engine stand and then to the front bumper. I then got the string tight and aligned to the center holes in the frame. Using a paper clip string and a nut tied on the opposite side of the string as the paper clip. I then hung the paper clips with the nuts on the string to get a visual of where I was in accordance with the center holes in the frame.

I then made a few more of my trusty paper clip and nut contraptions and where I was measuring I hung one to make it clear on the tape measure.

There are probably many ways to get the same results but cost wise and what I had on hand it worked well.

I did have a few measurements that were slightly different from one side to the other side of the frame.

Which makes me wonder. Does anyone happen to know what the tolerances were on these frames from the factory?

It was the late 70's/ early 80's. I'm guessing tolerance was like +/- 3"

 

[R.Hodges]

It was the late 70's/ early 80's. I'm guessing tolerance was like +/- 3"

😆 sad but true.