Right Stuff Rear Disc Brakes & Buick Wheels

Discussion in 'The whoa and the sway.' started by knucklebusted, Dec 24, 2010.

  1. GStage1

    GStage1 Always looking for parts!

    The problem you have is the bracket and not the calipers.

    The TSM kit I have on the site uses Ford Explorer rotors redrilled for our bolt pattern...there is plenty of clearance as shown in the article.

    I have attached a pic of a set of 71-77 El Dorado rear disc brake calipers and they have the outer pin hole chamfered (see black arrows) to clear the El Dorado rims...so if you need to remove 1/8" bevel on that section you should be fine.
     

    Attached Files:

  2. knucklebusted

    knucklebusted Well-Known Member

    Perfect! That's the piece I was missing! I had the local parts store pull every GM rotor they had on the shelf and none of them looked like what you had pictured. I tried 79 WS6 TA, 90 S10 4x4, 82 Camaro! It all makes sense now.

    Is there a particular year that works best? Redrilling does not present much of a problem if the axle and center register are workable.

    Thanks for the help!
     
  3. GStage1

    GStage1 Always looking for parts!

    The rotors are from the old body style Explorer.....92-99
     
  4. knucklebusted

    knucklebusted Well-Known Member

    Hmm, I got one of those to measure and it won't go over the axle. The height is good, about 4/10" taller but the axle would have to be turned down more or the rotor would have to have the inner drum turned out some more.

    At any rate here's a picture if anyone is curious and I've ordered a pair or rotors from TSM. Skip says they fit over stock axles and are Lincoln rotors. As long as they work, I'm in! Ford rotor is on the right in all pictures, Trans Am rotor is on the left. I also notice the fins are thicker and the rotor face is thicker on the Ford, too!
     

    Attached Files:

  5. N360LL

    N360LL milehi71Stage1

    What is the application on the Ford/Lincoln rotor? There are several of those that interchange with the sister chassis cars and trucks. And is it possible that a Ford caliper would solve some of the other issues as well?
     
  6. N360LL

    N360LL milehi71Stage1

    The 92-99 Explorer/Mountaineer rotor or is it a Expedition/Navigator rotor? What about a rotor or caliper from a Mk VII or VIII/ Mustang?
     
  7. GStage1

    GStage1 Always looking for parts!

    I was going by memory and I "think" Skip told me they are/were the Ford Explorer disc rotors......I would not think Lincoln is different since it use the same parts as the Ford Explorer.....Lincoln Aviator would be the same.....I doubt
    it is the full size Lincoln Navigator/Ford Expedition.....have Skip confirm.

    The rotors I have pictured in the article are redrilled to fit our bolt pattern:

    http://www.buickperformance.com/rrdisc.htm

    So, this means to me the Ford rotors are not a direct fit due to bolt pattern differences.
     
  8. knucklebusted

    knucklebusted Well-Known Member

    Oh, definitely. not a direct fit with the lugs needing redrilled but he says they clear stock axle diameter inside the hat without modification. Did you have to trim the axle outside diameter to fit those rotors?

    Stock is over 6.25" and the Trans Am rotor requires just a shade under 6.125" to work. The inside of the Explorer rotor is definitely smaller at a slim margin over 6" and that is probably just machining tolerances. It wasn't a lot but I don't know that I'd want to do it free hand.

    The rotor in your how-to looks like it should have been an Explorer rotor. It looked very similar to mine. If the bolt circle had of been 5x5 instead of 5x4.5, that would probably have been enough to clear out 5x4.75 axle. Similar to how the Seville was 5x5 and the TA rotor was almost identical except for 5x4.75.

    Not sure. I have been looking auto sites off and on for a while trying to find a rotor that will clear the mechanical dimensions and just get one redrilled. No luck so far.

    The TSM rotors should be here in a week so I'll know the story then.

    Its all good! I am glad I can keep the Buick chrome wheels and even get me some 15x8s made!
     
  9. knucklebusted

    knucklebusted Well-Known Member

    The new discs are here. I just need to get to the garage and see if they are the holy grail I've been looking for. For the record, they look an awfully lot like the Explorer rotors with the hats milled out a bit more.

    Pictures in a few hours.
     
  10. knucklebusted

    knucklebusted Well-Known Member

    Darn it! They still rub. These rotors do get a lot closer to working with a Buick wheel but they are larger diameter than the Trans Am rotors by 3/16" and the pin rubs the rotor. I've shaved enough off the pin boss that the middle of the caliper now will contact the wheel so I think I'm at the limit of that.

    If I use an 1/8" spacer, the wheel clears the caliper but by a fairly thin margin.

    Can I turn the rotor down to the size of the Trans Am rotor safely?

    Any other ideas? It isn't looking good for my Buick wheels at this point.

    Plus, depending on what happens, I'll have a set of new rotors for sale in the near future!
     

    Attached Files:

  11. knucklebusted

    knucklebusted Well-Known Member

    Still no joy with the TSM rotors though they shift the rotor/caliper farther from the wheel. Are those standard 15x7 wheels or are they perhaps WG types?
     
  12. GStage1

    GStage1 Always looking for parts!

    They are stock 15x7 wheels.......sounds like the brkt is the problem....maybe you should contact the vendor/manufacturer to found out what the problem is with their set-up and/or return the brkt/rotors and get the whole set-up from TSM....because we both know the TSM set-up works.
     
  13. knucklebusted

    knucklebusted Well-Known Member

    I really can't see how their bracket is going to clear any better. The brackets I'm using are from the Right Stuff kit and the rotor normally used is a GM from a 79 Trans Am. They are 11" diam. The Lincoln rotor is 11.25" and rubs the caliper pins of the RS plates. If the TSM plate was tall enough to clear the extra 0.125 radius, it would contact the wheel even more than the plates I have now. I've tried all 6 Buick wheels I have on hand and they all rub the caliper just before the wheel gets the level area of the welded in center. I'm going to have to use a spacer of at least 1/8" if I hope to keep factory style wheels.

    Even with the rotor touching the caliper pins, I can't get a business card between the caliper and the wheel in multiple places. Funny thing is if I take the outside pad off and slide the caliper toward the center, it clears.
     
  14. GStage1

    GStage1 Always looking for parts!

    The TSM brkt must be a different shape since it clears the stock rims. Only a side-by-side comparison will show the differences. Don't think a picture comparison will work.
     
  15. knucklebusted

    knucklebusted Well-Known Member

    I guess I'm basing the fact that the caliper is what hits, not the bracket. Currently, the caliper hits the wheel and the rotor hits the caliper pins. The caliper can't go any lower and it wouldn't be lower with the TSM bracket. The caliper can't go any farther inboard because then the outboard pad will have constant, significant drag on the outboard rotor face. There isn't a lot of rocket science here that a different bracket could correct. The only thing left is the caliper might be different but it sure looks the same and Advance shows the same part number for a Trans Am and a Seville for '79. Pads are the same, too! Hmm, 80 shows a different number on the Seville. Wonder if the only difference is the switch to metric?

    I'm getting the rotors turned down to 11" which should cause the pins to be free from rotor contact. Maybe that will let me get the caliper down as far as possible.

    For the record, if anyone needs a rotor like this, it is supposed to be an 82 Lincoln Continental rear rotor from the invoice.
     
  16. GStage1

    GStage1 Always looking for parts!

    That's the problem...you have the TA rear calipers and not the 79-85 ElDorado, Toronado calipers........Those 79 Seville and 79-81 Trans Am calipers are the same units. The bracket and brakes I show in the article are for the 79-85 ElDorado/Toro models. I can't remember the casting numbers exactly but I think they 060 and 061...the Sevilles from 79 are different and I think they are 450 and 451....looks like we have identified problem.
     
  17. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Here is a picture of the '77 Seville rear brakes I put on my Skylark. It's kinda hard tell from the glare, but I'm pretty sure the ends are bevelled off. They clear the 15x7 ralleys I have on my Skylark.

    [​IMG]
     
  18. knucklebusted

    knucklebusted Well-Known Member

    What rotor did you use? I am having a hard time figuring out how the Seville/Trans Am caliper is 1/4" thicker than the Tornado/Riv caliper when they use the same pads.

    Still some mystery here until I can get some things side by side.
     
  19. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    It's a stock 1977 Seville rotor. I pulled the whole rear axle from the car in the junkyard and simply had the rotor turned. Now FYI! The '77 had a 5x5 lug pattern (I had completely forgotten that until now, it could be a factor...), and in '79(?) supposibly it's the same rotor but just a 4 3/4 bolt pattern. If I ever go to aftermarket axles, I may go back to a 4 3/4 bolt pattern and my thoughts were to just purchase those Seville/Trans Am rotors and be done with the rear.

    (Then find the appropriate rotor's for the front to match the 4 3/4 pattern, my fronts are also 5x5 now)


    Is the caliper design effected by the difference in front wheel drive versus rear wheel drive? I've never looked at the rear end of a FWD Riv/Toro.
     
  20. knucklebusted

    knucklebusted Well-Known Member

    Dimensionally, I believe the Seville 5x5 and the T/A 5x4.75 rotor are the same except for the bolt pattern. The T/A & Seville use the same caliper as far as I can tell. I can't figure out how my standard axles, standard rear and standard 15x7 wheels rub so bad and others are working just fine. Crazy!

    BTW, I may have some T/A rotors to sell when I get this all done if you are interested.
     

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