After 20+ years with disc brakes on the rear of the 41 I'm thinking of going back to drum brakes. I've never really been happy with the Cadillac disc brake adjustment and parking/E-brake. Can anyone tell me if the 12" backing plates from a 70's Impala will bolt up in place of the stock 9 1/2" backing plates on a 74 Nova 8 1/2" 10 bolt. It would be nice to be able to go to the larger brakes
I appreciate that this info isn't directly addressing your question but I had to narrow my 10-1/2" 10 bolt by 2" to suit my new tire and wheel fit. By sheer luck I found that Aussie VN Commodore 28 spline axles were the perfect length and fit. But, I was also wanting to upgrade to rear discs and again by luck a pair of Aussie "Ford AU2" Borg Warner units became available to me, plus these brakes have a good performance reputation. The bonus was to now have conventional sealed roller axle bearings instead of the dangerous Chevy C clip style units. Long story short, I designed and machined a pair of new housing ends to accommodate both the Commodore axle bearing plus the AU2 backing plate ..... they got welded onto the 10 bolt housing. That gave me a 1500mm (59") WMS to WMS dimension. So, here's where I'm coming from .... maybe try to find another style 28 spline axle with an appropriate length, both Ford and GM are the same spline profile. There's then a good chance that commercially available housing ends could accommodate both the new axle bearings and suitable drum brakes. If you find an appropriate Ford axle, the Torino housing ends take a diverse range of bearing ID sizes plus 11" x 2-1/4" drum brakes. I apologize if this is too deep for what you are trying to achieve.
Both 70 Imp & 74 nova both use a 2 inch wide shoe , Rear Both have the 4-3/4 bolt circle Rock auto your Friend
I know that but my question is will the backing plates for the 12" x 2" brakes bolt up to the 8 1/2" 10 bolt which only has a 9 1/2"x 2" brake shoe. I know the drums are 4 3/4" bp and will interchange
I found talk on other sites , one Chevelle form ... My self I can not find a spec / measurement on backing plates. About 30-40 mints . I am like most just want to bolt on with little to No mods Now days Thats not all way's case ....if a difference's on flange mount , In my thinking & If I want to do I would take what ever size hole saw Cut the center of 10 B-P & 12 B-P Out , Tig weld the 10 Bolt into 12 bolt Backing Plate ... Or I wanted bigger rear dic , cardboard , plasma cutter Make my on kit mouthing brackets For bigger dic & caliper .. Not trying to be a Smart A$$ !! I make one off items , I have Tools , I guess most do not ... I also use the Cadillac calipers on 2 9 inch , both I feel fast rides 100 mph in 1/8 & Street drive 3,000 pd . Even set up 30 A with stock dic S-10 3:43 rear with 427 sb on plain Radial tire , 105 mph in 1/8 , did not break . On Sticks Yes I am sure it would have .
19eddy30, thanks for the reply. Yes sometimes you just need to modify something to fit. I had to reclock the Caddy brackets and add spacers in order to do the conversion
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