No drum to disc conversion for my buick

Discussion in 'The whoa and the sway.' started by thapachuco, May 12, 2020.

  1. Dan Hach

    Dan Hach Well-Known Member

    The OP asked about rear discs. The front brake does 70%+ of the stopping on a car. With weight transfer, it can be (much) more than that. As you reduce the weight on the rear, the brakes become less and less effective (because they lock up sooner). So adding a disc in the rear does nothing for you in terms of stopping power.

    As to drum brake sin general, once a tire skids, you're out of control. Adding a stronger brake on the front or back to make the tire skid sooner gets you nothing. Brakes can very effectively lock up the tires (under most conditions).
     
    Chuck Bridges likes this.
  2. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    I find it's easier to control a disc brake system over a drum. Much easier to apply pressure with out locking up. Driving a 4 wheel drum rig on a snow covered road makes that real clear.

    That being said, 4 wheel discs is more about keeping up with the Jones..
     
    knucklebusted likes this.
  3. knucklebusted

    knucklebusted Well-Known Member

    If the OP can find a weld-on bracket kit that suits him, I'm sure rear discs can be had. If you have access to waterjet, you could make one to suit yourself. Make a pattern for any big car kit and drill the holes you need to make it bolt to the backing plate holes. Rotors in 5x5 are not hard to source. Calipers will match the bracket you select. It is a worthwhile project.

    I will always prefer 4 wheel discs because they are faster to react, easier to control and harder to lock. A drum will self energize and grab the drum, causing it to lock much easier than a disc.

    Discs are not a gimmick and they will haul your car down more reliably and straighter than any drum brake setup can. I've owned every combination of brakes known to man and even without ABS, my heavier Stage 1 car will way out stop my 350 4-speed car with 4 wheel drums. I've since converted it to front discs and will put rear discs on it in the near future because it is much, much safer with equal tires and suspension.

    I'm willing to put my money where my mouth is with a contest at the next GS meet if we get to have one. My 70 Stage 1 4-wheel disc against any 4-wheel drum car you want to pull out. 70MPH to 0MPH, shortest distance wins. Cross the 1/4 mile line at 70MPH and stop as short as you can.
     
  4. Dan Hach

    Dan Hach Well-Known Member

    Interesting perspective and comments. It would be great to see a side by side comparison of the two systems.
     
    69GS430/TKX and knucklebusted like this.
  5. knucklebusted

    knucklebusted Well-Known Member

    Anybody got any pull with the track folks and set this up? Who wants to try to out stop me?
     
  6. Dan Hach

    Dan Hach Well-Known Member

    You'd have to throw about 10 sacks of cement in your trunk just to make it even if I did it :).

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  7. Tjmiller

    Tjmiller New Member

    I could not find any for my 67 Electra either, but I changed my rear axle to a 9” where disc brake kits are readily available.
     
    Lucy Fair likes this.
  8. bostoncat68

    bostoncat68 Platinum Level Contributor

    Aside from all the conversation around why drums are fine, I don’t see any conversation about buying new drums? I had a wonky drum on the rear brakes of my 68 Cat. Good luck getting a proper replacement. The ones I got from Kantner are total crap. The don’t come balanced and the thick hub material makes the studs too short. Used drums are just that, used and how do get a good set? The OP might be tired of trying to get something that’s easier to replace. Unlike A bodies, the parts are not always easy to get.
     
    69GS430/TKX and knucklebusted like this.
  9. knucklebusted

    knucklebusted Well-Known Member

    I haven't bought new drums. If my drum brakes need attention, they get converted to discs.

    I was reminded why I don't like drums yet again with the drum-in-hat E-brake on my Lexus. It takes more tools, more finagling and more effort to do drums at maintenance time. Disc are two bolts and a C-clamp. 10 minutes tops if the wheel is already off.
     
    Lucy Fair and bostoncat68 like this.
  10. Gary Bohannon

    Gary Bohannon Well-Known Member

    I bought "Muscle Car Brakes" ceramic shoe kit for my 67 GS. Original front aluminum drums and original rear iron drums.
    Stops better that it ever did. Feels about like my Nissan truck when I stomp them to test the feel. At the track, I can tell at the finish line when I hit them hard for the first pit road.
    Best my brakes ever felt (after 45 years with this GS).
    http://musclecarbrakes.com/
     
    Last edited: Dec 5, 2021
    69GS430/TKX and SpecialWagon65 like this.
  11. SpecialWagon65

    SpecialWagon65 Ted Nagel

    I've done several cars with MuscleCarBrakes. Premium product, all my A bodies get these shoes. Did my Special Wagon with these 20 years ago, still one of the best braking cars in the fleet.
     
  12. lemmy-67

    lemmy-67 Platinum Level Contributor

    The front disc conversion on my 67 used GM/Mopar parts for the calipers/rotors with the stock drum spindles. The shop fabricated custom mounting brackets for the calipers, and bolted it all together with braided steel lines using the stock master cylinder & prop. valve. I kept the rear drums as-is. In over 10 years of driving them, I've had the front pads & rotors replaced once, that's it.
     
    69GS430/TKX likes this.

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