Underbody Dimensions

[Peter]

I am new to the site. I found underbody dimensions on the site and when installing rear frame/torque boxes I found the rear spring rear hanger hole measurement approx 1 1/2 inches different form the original. The rest of the measurements matched the car pre disassembly. The drawing showed 15.03 from baseline. Any comments are appreciated. It is a 1972 Grande.

Thanks

 

[Sheriff41]

No help on your question but welcome to the forums.

 

[Bentworker]

There are two sets of conflicting underbody dimensions floating around on the forum

 

[Hemikiller]

The 71 manual calls out 11.74. Not sure where that came from, but it's incorrect.



'73 manual has the correct dimension at 15.03"



You might have some poorly formed frame rails. Are you doing one side at a time, or both at once?

 

[Peter]

The 71 manual calls out 11.74. Not sure where that came from, but it's incorrect.

View attachment 72753

'73 manual has the correct dimension at 15.03"

View attachment 72754

You might have some poorly formed frame rails. Are you doing one side at a time, or both at once?

Purchased new frames/torque boxes from National Parts Depot and they match the originals. I have removed both frames but took a lot of measurements. The rear cross member is still in tact so i have a reference for the rear of frame for height. I did a dry fit and all pieces align very well. All measurements match except for the 15.03. Scratching my head on this one. Thanks

 

[IA Rider]

I installed the NPD rear frames on my car. I purchased them in 2013. I hope they have improved the quality. I also replaced the full trunk at the same time. Here is a link to my frame rail install. https://7173mustangs.com/threads/ia-riders-73-mach-project.13885/page-2

 

[Peter]

I clamped new rear torque boxes in place as per measurements taken prior to removal. I was hoping to verify as per the attached drawing I found on the site but was scratching my head at the horizontal measurements (the vertical ones are straight forward). The torque boxes match the drawing if I add the red circled dimensions together (66.86 + 11.15 = 78.01). Did I read the drawing correct? Also, not sure what the A represents at the end of the dimension (listed on the forward 4 dimensions).

Any help reading the horizontal measurements is appreciated.

Thanks