MyFriendScott
07-03-2011, 06:36 AM
One of the goodies that came with the purchase of my friend Scott's '67 Camaro was a spare 12-bolt with original Eaton posi, and 3:73's (Richmond gears, not factory). The axle flange to axle flange measures 60" and I believe this should be the same distance as the 10-bolt in the car now. I used this link as a reference:
http://www.quickperformance.com/Technical%20Info/sus_measure.htm
The leaf spring perches have a centering pin hole in them so I'm guessing based on the info and decoding the numbers, this 12-bolt came from another Camaro or Nova. Since Scott also had a highly modified '69 RS, it might have been the original 12-bolt that came in that car before he stepped up to a new unit. Of course, I can't ask him now so it's all been decoding numbers on the axle housing, removing the diff cover, and also spinning the yoke and counting the axle revolutions to determine what I have.
So...Since I'm stepping up to a new tire/rim combo that's 1" taller than what's in the car now, I decided now would be as good a time as any to get the 12-bolt ready to gain back the gearing and the obvious other advantages of using the 12-bolt. One thing I haven't measured yet are the spring perch distances to make sure there are no surprises.
Are there any other areas I need to consider as I prep the 12-bolt for the swap? Can I still use a mono-leaf made for a '67 in this axle if it is in fact from a '69 Camaro? Are the leaf widths different? I'm pretty sure the '67 monoleaf that's in there now doesn't use a centering pin either. Thanks in advance for all/any advice.
http://www.quickperformance.com/Technical%20Info/sus_measure.htm
The leaf spring perches have a centering pin hole in them so I'm guessing based on the info and decoding the numbers, this 12-bolt came from another Camaro or Nova. Since Scott also had a highly modified '69 RS, it might have been the original 12-bolt that came in that car before he stepped up to a new unit. Of course, I can't ask him now so it's all been decoding numbers on the axle housing, removing the diff cover, and also spinning the yoke and counting the axle revolutions to determine what I have.
So...Since I'm stepping up to a new tire/rim combo that's 1" taller than what's in the car now, I decided now would be as good a time as any to get the 12-bolt ready to gain back the gearing and the obvious other advantages of using the 12-bolt. One thing I haven't measured yet are the spring perch distances to make sure there are no surprises.
Are there any other areas I need to consider as I prep the 12-bolt for the swap? Can I still use a mono-leaf made for a '67 in this axle if it is in fact from a '69 Camaro? Are the leaf widths different? I'm pretty sure the '67 monoleaf that's in there now doesn't use a centering pin either. Thanks in advance for all/any advice.