How to improve braking performance (semi-DIY)

Discussion in 'News and Features' started by Izso, Sep 21, 2011.

  1. keegs

    keegs 5 Year | Silver

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    I see, now i remember...AD08 is the replacement. Cool, coz I've been looking for a good set of tyres. My concerns are on wet road grip. Need speed and grip in the wet...haha.

    Any plans to install steel-braided hoses?
     
  2. ariolz

    ariolz 5 Year | Silver

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    Re: How to improve braking performance (semi-DIY) part #1


    Poor Tenaga box :D
     
  3. Izso

    Izso Boooooossst
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    Re: How to improve braking performance (semi-DIY) part #1

    Plenty of good wet road grip tyres out there. Michelin PS3, Eagle F1, etc.

    And yes - steel braided hoses is in tow! As I mentioned in the opening paragraph la.


    SSsssssShhhhhhhhhhhhhhhhhhhhh :flute:

    ---------- Post added at 12:50 PM ---------- 6 hour anti-bump limit - Previous post was at 12:46 PM ----------

    There's some debate about changing to high performance brake pads and changing to twin pot calipers.

    Depending on what you mean by "high performance", RS makes 900 degree "high performance" brake pads. These pads work wonders on the track but most likely be useless on the street since most "performance pads" need warming up before they start to grip. But if you take a EBC Ultimax "high performance" pad and compare with my lowly Bosch pads, then of course the EBC Ultimax is better.

    And changing to twin pot usually should be followed with changing the brake servo and not forgetting the proportioning valve, otherwise you might get the "on-off" brake effect with the twin pots.
     
  4. TitanRev

    TitanRev ModMod
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    Coefficient of Friction is best use to describe the braking efficiency. For a brake to work efficiently we have to look at it from a bigger picture. A few things that governs the efficiency of a brake.
    Types of rotors & size, pads, hose, fluid, caliper size and pump force...etc...etc..

    As discussed by all the guys, Brake uses friction to stop a moving object and hydraulic pressure with the help of vacuum servo is the medium to create friction in a brake system. The higher the pressure, the higher the friction. The higher the friction then it will create more heat, choosing the right temperature of pads to use there for its important as some high performance pads will have high temp rating but it will not work on normal daily drive because the pads material needs to get up to operating temperature to work efficiently.

    Having said the above, for a brake to work efficiently we also need to know how to transfer the brake pressure efficiently. Does the brake pistons get all the brake pressure it supposed to get? Brake pressure can be lost in the transfer process due to heat and expansion.

    Then, there's the road condition, tire's condition...which also contribute to braking efficiency. Even with a 4 or 6 pot...you still won't have a good braking efficiency on ice is you are not using winter tires...

    So choose your pads & rotors depending on your usage...

    Just my 2 cents
     
    #24 TitanRev, Sep 22, 2011
    Last edited: Sep 22, 2011
  5. kcng

    kcng Senior Member
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    LoL
    I just notice its a tenaga box...

    i was under the impression that it was the "kerb" thing u put over the drain....
    LOL
     
  6. chinozie

    chinozie Very Young Member... :D
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    Nicely done...with pictures too...:adore:

    Just to add some info...

    For Safety reason ,Make sure use a jack stand...don't just leave your car on car jack, or at least put the tire below your car frame...and do pull the handbrake...small changes, big different...safety first...

    Once done with the installation...do a Brake Bed-in for maximum grip.


    Happy DIY ! :driver:
     
  7. Izso

    Izso Boooooossst
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    Yeah.. the bead-in process is part of #2 but I lost my photos so gonna have to re-take some photos to compensate.
     
  8. me2kimi

    me2kimi Senior Member
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    Hi bro, my wife myvi brake is operate abnormally. I have to pump the brake until felt the brake bit. Then, when I put my feet on the pedal for a long time, the pedal start to go floor, same as when sudden braking. The pedal will straightly went to floor.

    What wrong with the brake? I've bed-in the brake before but problem still occurred.
    Please advice
     
  9. TitanRev

    TitanRev ModMod
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    me2kimi, There's probably a pressure leak in the brake system. You need to pump the brakes a few times because there's not enough pressure in the lines.

    For the pedal went straight to the floor you might have a leaking vacuum servo or a master cylinder problem. IF its the master cylinder problem the piston's oil seal inside the master cylinder is causing the problem.

    If you felt that you have a spongy brake pedal. It might be the brakes are not bleed properly and there's air inside the brake lines. Also do change the brake fluid on time as DOT5 below brake fluid will absorb water over time and causing the fluid to work badly.

    Hope it helps
     
  10. me2kimi

    me2kimi Senior Member
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    Bro TitanRev, I just check with vacuum gauge. I got 18 in.Hg at idle. I think it is good reading for vacuum.
    And the brake can function perfectly at park position.
    When this problem occured, I notice that cap oil seal for brake fluid putus already. Then changed it from hulf cut shop but with fifferent type seal. Does this cap play major role in brake operation?
     
  11. Izso

    Izso Boooooossst
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    For this sort of problem i'd check two things.

    1. Is your oil level consistent or does it drop? If drop means you have a leak in your system somewhere.
    If not it's probably time to bleed the air out of the system.

    2. How old is your brake hoses? If old and cracking you should change them. What mods have you done to the brakes? Did you change the servo?

    All really depends on the condition of the above.


    I just remembered something. Did you take out the calipers like I have? Did you ensure left and right positions are correctly installed? Make sure the bleed nipple valve is facing upwards not downwards. If downwards the problem is with your caliper install - it's reversed
     
    #31 Izso, Sep 22, 2011
    Last edited: Sep 22, 2011
  12. drexchan

    drexchan Senior Member
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    He need to get his master pump cylinder serviced with compatible parts, not something from halfcut.
     
  13. me2kimi

    me2kimi Senior Member
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    1- The oil level is steady and I already bleed it out without taking out caliper. Problem is still there.
    2- everything is in stock condition and that myvi is 2006. So I think is 5 years already. Servo also original from P2.

    Bro, I only get the cap from chop shop coz spare part did not sell cap only. After replace the cap, the bleeded the brake.

    p/s: only cap from chop shop, not entire servo assy
     
    #33 me2kimi, Sep 22, 2011
    Last edited: Sep 22, 2011
  14. deliquent

    deliquent Senior Member
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    great DIY effort... thumbs up bro... :proud:
     
  15. Izso

    Izso Boooooossst
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    I still think there's a leak somwhere. Should consider getting the original cap from Perodua as it's not expensive mah. For the pedal to sink all the way in like that either your servo is completely kaput or you're running a leak. Since the oil level is steady it sounds like the weakspot is cap. Or do you have a jammed rear drum? My wira had a jammed drum at one time and the pedal did exactly that.
     
  16. me2kimi

    me2kimi Senior Member
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    Servo is the black round part right?
    I think drum is still in good condition coz it operate perfectly by using handbrake.
    (no problem while park at my house with ramp ground)
    I'll try source new oil cap first.

    BTW, while bleeding the brake fluid, why there is a constant bubble coming out from nipple?
    Is is normal? Or got leak somewhere?
     
  17. VectorX2

    VectorX2 5 Year | Silver

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    try bleed a couple more times after some braking intervals
     
  18. me2kimi

    me2kimi Senior Member
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    One more thing forgot to mention, it's got an ABS. And during bleeding, once press the pedal has to wait few seconds to pedal rise up the can push it back. Cannot continuous pumping the pedal.
     
  19. chinozie

    chinozie Very Young Member... :D
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    Nice !

    Keep it up with you great updates...
    now days we're lacking of tech talk...:banghead:
     
  20. Izso

    Izso Boooooossst
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    Wow.. I'm thinking you might need to service your servo. Perhaps the seals there are spoilt.

    Best you bring it to a mech to diagnose. Don't delay the brake repairs! It's the difference between stopping in time and smashing into a car!
     

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