I've got a 12 bolt from a 71' Riviera . What mounts will I need and where to get them ? How much narrower . Figured Moser Axles would do just fine . Some input here would be great ! Thanks, Happy New Year ! Steve
I pretty sure that that rear end is not a direct swap. A Riv. is not a GM A-body, the rear is probably wider, mounts will not line up, and I'm pretty sure that the Riv. wheels have a larger bolt pattern, limiting wheel choices, than one from a 64-72 GM A body. Whats wrong with the rear you have? Gary G.
A Riv. 12 bolt is a completly different rear than an A-body rear. As in nothing is interchangable. Gears, axles, yoke, ect. They are like comparing a dana 60 to a dana 30.
12 bolt big rear in an A Body Hey Gary , My rear end is an open 2.79:1 8.2" . The car may not be raced but I'm sure it'll get hammered every now and then . :3gears: I wasn't sure if the 8.2 could stand up to a mildly warmed up BBB . I know that the 12 bolt would need to be cut down and the mounts for the lower arms , springs and shocks repositioned . I was wondering if it can be done, where to get the parts ,and whether or not it's worth the trouble . I know that I can get the ends for the tubes and have axles made . One thing though that concerns me still is the upper rear control arms . The frame mounts are fixed and set up for the 8.2 , I imagine the upper rear "ears" on the 12 bolt are wider. I think the upper rear arms would be put into a bind trying to get them mated to the 12 bolt without doing something about that . I haven't even been under the Riv . to see what's there . Can I get the large bolt circle front rotors for an A-body disc conversion or would I have to have the A-body rotors drilled ? Got some major "Hunnie Do's" starting up soon . Cold weather is here and I do the major yard work , construction etc. in the fall/winter & spring before the heats back up . Getting ready to re-insulate the house and install new siding , 100 sheets of OSB / Hardie Panel going up . My winter is spent before it gets here . :af: But maybe our $200+ a month utility bills will come down next year . Thanks guys , Hope you all have a safe and happy New Year ! Steve
Steve, the '71 Riv rearend is a '71+ 9 3/8 Buick rear, & besides the width issue, differences in welded perchs, bolt pattern, flat style pinion flange, etc, the cast upper perchs are totally different spot. Absolute big $$$ nightmare to adapt. Set on installing a 12 bolt in the '64, you will need a true A-body 12 bolt, easiast fit is one out of a '65 or '66 Chevelle or Elco. Either year housing will be expensive as they are highly sought after. The '67-68 & slightly wider '69-72 "chevelle" 12 bolts will also work. Looking for something more durabile than a stock posi c-clip axle 12 bolt, you'll be better served looking at a built-up 8.5 10 bolt. The 8.5 can be procured & propperly built from mild to wild for less than any upgraded bolt-in axle 12 bolt. Got Posi? :3gears: Roger
12 Bolt Woes Hey Roger thanks for the heads up . Is that 12 bolt I've got worth anything on the market ? I'm not into throwing good money after bad . It would be a shame if I junked it after I've taken what I need . Would I be whistling in the wind (wasting time / money) building this 8.2" that's in my 64' ? Thanks , Steve
8.2 If your car is a street dweller the 8.2 is a good rear and will hold up fine under street operation. If your going to bolt on slicks and start dumping the clutch at 4000 rpms or trans braking the car etc. then think on spending your money else where. They sell posi unit for this rear and even a good set of 3.36 3.23 or new 3.55 3.90 depending on your style will work well with all new bearing. 750 for all new stuff parts and as low as 600 if you find a deal on some used gears. sometimes you can find a stock posi unit cheaper...BUT if your going to keep the car spend some money on the rear...you will be a way happier camper in the long haul. Jim
