Disc brake drag

Discussion in 'Race 400/430/455' started by flatire, May 31, 2011.

  1. flatire

    flatire Well-Known Member

    any ideas on how to reduce brake drag?
    It's not excessive.
     
  2. BQUICK

    BQUICK Gold Level Contributor

    Springs on the pins.....been putting them on for 30 yrs. Go to hardware store and get a medium rate coil spring and some washers. Take a while to find the right combo of length and rate but worth it.

    Also, ditch the rear self adjusters ...I was pushing my 3700 lb GS in the staging lanes Sunday by my little 150 lb self.

    Synthetic wheel bearing grease and gear lube helps to.:TU:
     
  3. flatire

    flatire Well-Known Member

    Yeah, i like the spring idea.
    Good thinking to ditch the rear adjusters too.
    thanks!
     
  4. tlivingd

    tlivingd BIG BLOCK, THE ANTI PRIUS

    Is there just enough to take the pads off the rotor, or will it move the pad and piston fully back into the caliper?

    It could be really bad if the second happens and your not expecting it.
     
  5. flatire

    flatire Well-Known Member

    I just inspected my calipers and there isn't any room for springs, they'll rub on the rotor.
     
  6. SteeveeDee

    SteeveeDee Orange Acres

    Do not put return springs on the front disc brakes. :Smarty: If you do manage to fit them, and the pads are worn, they will require serious travel to get back in contact with the rotors. Neglecting the fact that the wiping action of the pads on the rotors is what provides safe braking in wet weather, that travel may allow the rears to lock up first, or at least give you a really low pedal. If you do this and get in a wreck, you will be liable for it if it is a contributing factor. You don't see any cars coming from the factory with return springs on the disc brakes, for a reason. Yes, they rub (unless your wheel bearings are loose enough and push the pads away from the rotor, again potentially leading to a low pedal condition). They will also cost you a minimal amount in mileage. If your wheel can be turned by hand, the pads are not rubbing enough to be a problem. If you can't turn it by hand, they should be repaired. I wouldn't know the cause from behind my monitor.
     
  7. Dstoltenberg

    Dstoltenberg Well-Known Member

    Never heard of ditching the rear adjusters... wouldn't that cause the drum brakes to bind up?
     
  8. flatire

    flatire Well-Known Member

    I can't get the springs on the type of caliper i have, they would rub on the rotor. I think my calipers fit a 80's malibu, i forget the part number.
    What type of calipers do you run?
    Thanks!
     
  9. flatire

    flatire Well-Known Member

    The idea being they don't self adjust. Just do what ever is SAFE and will eliminate the self adjusting, i figure.
     
  10. flatire

    flatire Well-Known Member

    Right, safety first! :Smarty: As long as you run your dial.:TU:
     
  11. SteeveeDee

    SteeveeDee Orange Acres

    Leaving the adjusters off the rears to minimize drag is a perfectly acceptable thing to do, though. Self adjusting brakes didn't use to exist, after all.
     
  12. BQUICK

    BQUICK Gold Level Contributor

    I have 70-72 single piston calipers.

    The springs need to be low tension and a close fit to the pin. They do not fully retract the pistons. Again, takes some hunting to find just the right ones. But.....to a racer it is well worth it. There will be a slight increase in pedal travel. I can stop my 3700 lb GS fine in the 1/4 from 130+ with MANUAL disk brakes.

    And....I love how I can jack the car up and spin the front tires many revolutions with one stroke.

    As far as the rears, again there will be a slight increase in pedal travel and they will be periodically re-adjusted with a brake shoe caliper (or trial and error adjusting).

    I was at the track one time and the car wasn't consistant, slowing .03 every time I'd back up until it was over a tenth slow. The adjusters were doing their thing tightening up.....
    Never ran self adjusters again on any car I raced.....
     
  13. SteeveeDee

    SteeveeDee Orange Acres

    OK, for a dragster springs like you are using make sense. You will have the travel under control. But I was talking street use earlier.
     
  14. flatire

    flatire Well-Known Member

    I believe i have the same calipers. Wow that would be a tight fitting spring.
    I guess the search is on.
    Thanks!
     
  15. Schurkey

    Schurkey Silver Level contributor

    Wouldn't it be safer to just use factory low-drag calipers and the matching quick take-up master cylinder?


    Disabling the self-adjusters on the rear drum brakes? Really? Can you even measure the difference in the quarter-mile times?
     
  16. BQUICK

    BQUICK Gold Level Contributor

    The spring are not a safety issue, they just lightly pull the pads back quicker than they naturally would. Most newer car have this feature designed into them.

    I've worked on many cars that the rear self adjuster were tightening too much and in thoses cases, yes there was an ET and MPH improvement.
     
  17. TomGS72

    TomGS72 Silver Level contributor

    BQUICK,

    Do you have a picture of the spring set up, or at least a picture of the spring only, so I know what to look for? I have 1972 calipers/rotors on front.

    Thank you.

    Tom
     
  18. BQUICK

    BQUICK Gold Level Contributor

    I'll take a pic ASAP

    Bruce
     
  19. Rich Johns

    Rich Johns Platinum Level Contributor

    Looking forward to some pics
     
  20. Schurkey

    Schurkey Silver Level contributor

    Quicker, or FARTHER?

    Name one that doesn't also have a quick-take-up master cylinder to deal with the additional fluid displacement needed to get the pad back to the rotor.
     

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