Larger Rear Brake Rotors?

Discussion in 'Brakes, Wheels and Tires' started by VoodooBoss, Dec 1, 2013.

  1. TMSBOSS

    TMSBOSS TMO Addict

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    Maybe yes, maybe no.

    If you move the calipers out you should have more effective braking. The lever is longer.

    If you are replacing worn out rears, the cost difference is not that much.
     
  2. cholmes1

    cholmes1 Charles

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    Has anyone found any solutions to the rear brake noise? It appears to be somewhat mixed in those that have it and those that don't, but would like to know the best/quietest pads and rotors to apply during installation. For reference there will be 98% street use and maybe 2% track use on the system.

    Thank you for the help.
     
  3. KNS Brakes

    KNS Brakes TMO Race

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    Not singling you out - just pointing out a common request we get. As far as noise goes - street pads are usually quiet and track pads are not. Well bedded pads/rotors are more quiet than those that are not and light braking is usually louder than hard braking. Race pads will 'unbed' if used cold or on the street a lot.

    "" For reference there will be 98% street use and maybe 2% track use on the system""

    There is really no such thing as 'light track' You are either repeatedly braking hard (like on track) or you are not.

    If you are getting noise from street pads - try bedding them a bit. Or flip them around and re-bed.

    Ken
     
  4. cholmes1

    cholmes1 Charles

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    I appreciate the insight. I have not yet bought any of the components so I will look at getting the StopTech slotted rotors you recommended above and pair them with street pads. Any recommendations?
     
  5. KNS Brakes

    KNS Brakes TMO Race

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    Stoptech makes a good rotor and so do we. Our KNS rotors made by DBA are premium blanks. (shameless plug)

    For street pads - the range is fairly narrow but there are differences. I could go on - but..

    Ceramics - quieter/softer/more pulsing issues especially when overheated/used hard

    Semi metallic - louder and some dust - but reliable and predictable.

    There are always exceptions.

    Carbotech makes a damn good low dust street pad

    Brembo calipers are VERY noise prone

    Hawk HPS 5.0 are a bit overmarketed/priced - but they are a decent reliable semi-performance street pad that rarely disappoints. Sold them since day one.
     
  6. Fabman

    Fabman Project: "Frankenstang"

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    I think I see your problem....the pads are missing. ;)
     
  7. F.D. Sako

    F.D. Sako TMO Addict

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    Question, does the full pad surface area make contact with the rotor, or is there some pad overhang?

    Looking at the pic above, it looks like there may be some pad over hang that could cause binding, similar to using Mcload clutches with the stock flywheel.
     
  8. k98dave

    k98dave TMO Addict

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    I have these, no overhang with stock Ford pads.
     
  9. Surfergeek

    Surfergeek TMO Race

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    Bringing this thread back from the dead and seeking some additional input.

    I currently have the Steeda 13" kit on the car, it went in before the GT500 solution was really readily available. Only 1 source for rotors and that's Steeda with their custom DBA rotor.

    Since switching to Pagid pads front and rear, been having issues with the rear brakes. Moaning and calipers hanging up in reverse, grinding sounds on track with vehicle weight transfer under acceleration while turning (not during braking) and it's caused me to look into this some more.

    Basically decided to go one of 2 directions.

    GT500 brackets and GT500 rotors - 13.8"

    Or

    Go with something like the GiroDisc 11.8" rotors, but take advantage of it being a 2 piece design and significantly lighter. Giro Disc comes in under 10lbs, while a GT500 rotor pushes a little over 16lbs.

    I have gotten good feedback on their durability.

    Is the lighter weight and 2 piece design of the GiroDisc more advantageous than the perceived advantages of the larger rotor with more surface area of the 13.8" but a 1 piece design and heavier?

    I am for now running Pagid RST-3 up front in factory 14" brembo and RS29 in the rear. Next change is a true race caliper in the front, but haven't decided on that one yet.

    Any input from the experts here? Seems to me that lighter 2 piece floating rotors bring more advantages than the larger GT500 rotors with the brake bias being so heavily to the front. But that's my totally not an expert opinion from reading lots.
     
  10. ArizonaBOSS

    ArizonaBOSS Because racecar. Moderator

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    Before you make a wholesale change, check your rear pads; post a photo of the "centering pin" on the pad (that interfaces with the piston). I had one set of pads (albeit not Pagid) where the pins were too tall from the manufacturer and this caused the rear brakes to drag with no pedal applied. My "solution" was to file the centering pins down. Worked great. Might not be your issue but it's worth checking before you spend $$$.
     
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  11. Surfergeek

    Surfergeek TMO Race

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    Thanks for the input, definitely wanted to check everything out, and had the whole rear end gone through and rear brake assemblies checked from top to bottom when the car was getting serviced and prepped for tracking this year. Changed the rear calipers, full brake service, Everything seemed to be okay, rotors are close to end of life, but will definitely have that checked out too. Rear rotors are due for replacement soon due to wear, and I still have my factory brackets, so changing back to 11.8" rotors is just a matter of doing the work and acquiring the new rotors. I need to buy new rotors regardless, it's just which route am I going to go.

    I also have some less aggressive rear pads that I can swap in to see if issues go away with those too. But I haven't been able to read of any widespread issues like I have been having with the Pagids in the rear at an RS29 like I have been using which makes me think it's something else about the set-up.

    What's interesting is the major complaint is the reverse, with the brakes lightly applied, any grinding/sticking in the rear goes away, brake not applied and it can get pretty gnarly.
     
  12. TMSBOSS

    TMSBOSS TMO Addict

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    I have run both the Pagid and Girodisc set up along with the GT-500 rears.

    I find the GT-500 set up to provide better braking. The Girodisc set up was good, rotors lasted for ever but gave no noticeable improvement in brake feel.

    I run the blowfish brackets.
     
  13. VoodooBoss

    VoodooBoss Rick Moderator

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    I had noise with my GT500 rear brake setup as well. Switched back to stock rotors and it disappeared.
     
  14. Surfergeek

    Surfergeek TMO Race

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    Hadn't seen the blowfish brackets yet, those look pretty trick. Nice weight savings if you run those along with giro disc rotors in the rear.

    No issues with the brackets?
     
  15. TMSBOSS

    TMSBOSS TMO Addict

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    I bought a set when Steve first offed.

    No issues. I had to sand and bed the rear pads after some pulsing. Not a bracket related issue. I failed to bed after install.
     
  16. Daveyboy

    Daveyboy TMO Intermediate

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    Just read this whole thread. A lot of good info. I do have questions. I would like to do the GT 500 rear swap on my 06. Do I only need rotors and the Gt500 calipers? Or do I need calipers as well. Also saw a brief mention of rear brake cooling. I have never seen this done. Is it possible to see som pic? Pm on that would be fine.
    Thanks, Dave
     
  17. ArizonaBOSS

    ArizonaBOSS Because racecar. Moderator

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    If you are going the GT500 rear brake route, you only need the rotors and the brackets. The calipers are the same; although it would probably be worth looking over your calipers and seeing if they need to be rebuilt or not, assuming they are still the set that came on the car from the factory.

    The GT500 calipers (like the BOSS 302 calipers) have a different part number simply because they are painted black; mechanically all the OEM rear calipers for S197 are the same (although there is some mention of a possible casting change in the link below--do your research).

    Also here's a link to a "one-stop" shop for the conversion kit: https://vorshlag-store.com/collecti...7-mustang-13-8-gt500-rear-brake-upgrade-kit-3
     
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  18. OPMustang Tim

    OPMustang Tim TMO Race

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    Ford still offers reman calipers (Motorcraft)show they fit the Shelby but they do not come with brackets then they have GT calipers that come with the brackets that do not specify '13-14 GT500. Anything '10 and newer should clear the bigger rotor. The Ford Reman stuff is still 'cheap' at this point (Less than $200pr). I would use @pufferfish relocation brackets.
     
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  19. Daveyboy

    Daveyboy TMO Intermediate

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    Thanks for your input. I have seen that kit on Vorshlag's page before. I have also read he entire thread on their old Mustang. I had some apprehension about the rear calipers because that car was an 11'. Probably will order a set of calipers for the GT 500 and compare. Mine are close to being toast....not the good kind of toast either.
     
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  20. 302 Hi Pro

    302 Hi Pro Boss 302 - Racing Legend to Modern Muscle Car

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    I have an old 2012 Boss 302. I ordered & installed the individual OEM 2013/14 GT500 rear brake parts. I do remember a slight brake squeal during the first 500 - 1,000 miles but silent operation since then. (Did not pre-bed.)

    Very happy with performance after several years and 10k plus miles and they look good too.
     

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