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drum to disc backing plate question

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Old 01-02-2017, 02:16 PM
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drum to disc backing plate question

I bought the Baer 2302048 13" rear rotor kit for 93-97 Fbodys. Link at bottom.

The kit did not come with the adapter brackets but instead came with two brand new backing plates. My 10 bolt is a drum setup so I need to know if I can use these backing plates or not. I assume I will have to cut the top ear off the axle housing and redrill 4 new holes but will these backing plates give me the correct offset for the rotors and calipers or will I still need to buy shims and spacers (link below). Shims and spacers would run me $110 plus shipping. I guess Eds hassle free backing plates for $85 seem like an easier option and I can try and sell these backing plates. Problem with buying from Ed is he never gets back to me so I dont want to buy stuff from his site and never get the parts



http://www.jegs.com/i/Baer-Brake/136/2302048/10002/-1


place that sells shims and spacers http://www.andyz28.com/catalog.htm



Last edited by BOTTLEDZ28; 01-02-2017 at 04:08 PM.
Old 01-02-2017, 08:09 PM
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Re: drum to disc backing plate question

I'm sure that more than a few drum rears have been converted to discs without the concentric ring spacers. The shims may or may not be necessary, you won't really know until you go to bolt on the caliper.

If I remember correctly, the two bottom holes in the drum backing plates line up with the disc brackets, the holes just need to be enlarged. The top two have to be drilled to match the disc brackets.

I ordered some parts from Ed this fall. Took awhile (weeks, not months) to get here, but they did show up.
Old 01-02-2017, 08:20 PM
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Re: drum to disc backing plate question

Originally Posted by Drew

I ordered some parts from Ed this fall. Took awhile (weeks, not months) to get here, but they did show up.

Well thats is reassuring. This will be my winter project or possibly early spring. I need to see if I have enough room in my garage to slide my axles out based where the car is resting right now.

maybe I should just order Eds backing plates and then try and sell these Baer ones. I need Ebrake cables anyway so I might as well just order everything from one place.

My only dilemma will be finding out I have to machine the axle flanges to fit inside the rotors.
Old 01-02-2017, 09:14 PM
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Re: drum to disc backing plate question

I'd hold onto what you've got until you've got the other parts in hand, just in case.

I've read conflicting reports about rotors and drum axles. There's enough difference between brands of rotors, I'd probably try it and see.
Old 01-02-2017, 09:30 PM
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Re: drum to disc backing plate question

It takes longer to remove the drum backing plate than to cut off the top of the bracket and drill 4 holes to mount new bracket
You always want to center the caliper abutment bracket on the rotor w shims no matter what.
I have rednecked fitting the axle flanges in the rotors b4. Jacked car up, set on stands, pulled wheels/brakes down to axles, fired up car, put in gear and ran the grinder on the axle flange down til the rotors would sit flush. That was 20 plus yrs ago. Still working like a champ.
Old 01-02-2017, 09:45 PM
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Re: drum to disc backing plate question

Originally Posted by TTOP350
It takes longer to remove the drum backing plate than to cut off the top of the bracket and drill 4 holes to mount new bracket
You always want to center the caliper abutment bracket on the rotor w shims no matter what.
I have rednecked fitting the axle flanges in the rotors b4. Jacked car up, set on stands, pulled wheels/brakes down to axles, fired up car, put in gear and ran the grinder on the axle flange down til the rotors would sit flush. That was 20 plus yrs ago. Still working like a champ.
Are you suggesting buying those shims/spacers from that AndysZ28 site and using the backing plates I already have versus buying Ed Hassle free brackets?

I have no problem cutting the top off the drum backing plate on the housing and drilling two new holes as well as enlarging the lower two. Thats an easy job as long as I can center the new Baer backing plates. This is where the shims and spacers come in BUT its $100 for them versus the $85 Hassle Free brackets from Ed. I assume Ed sends washers with his backing plates to help the end user center the abutment bracket over the rotor.

I'm just trying to weigh out my options before I tear into the car this winter. Im almost sure I will have to have the axles turned down since the Baer rotors have the tapered hat design.
Old 01-02-2017, 09:48 PM
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Re: drum to disc backing plate question

For anyone else reading this thread and wondering what I am referring to when I say shims and spacers, please refer to this thread.....https://www.thirdgen.org/forums/brak...m-o-e-j65.html
Old 01-06-2017, 04:39 PM
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Re: drum to disc backing plate question

I have C4 Wilwood hats, which is what you'd use with Ed's stuff, but I have Baer backing plates for 13" rotors. I would just return the Baer (overpriced anyway) and get some Wilwood for the C4, it is the proper offset and should work with the stock axle flange. I can get measurements if you want, I'll just have to find everything since I put it all in the basement after I tore the car apart.

Oh, wait. I may have 12" rear brakes, but the Corvette stuff should still be what you'd use

Last edited by scooter; 01-06-2017 at 04:43 PM.
Old 01-06-2017, 06:02 PM
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Re: drum to disc backing plate question

I am running Baer rotors up front so I wanted matching rotors for the rear. I paid just over $400 for these. I couldnt say no to that. I already have a pair of NOS GM calipers that were pulled from a brand new rear axle at my local dealer.




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