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DefSport 12.2" Brake GB! Round 5 - 2015!!!

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  • DefSport 12.2" Brake GB! Round 5 - 2015!!!

    Seems like there's enough interest out there for another GB round. Pricing if we hit 6 full kits is $950 shipped WITHOUT ROTORS (shipping cost kills it). This includes Hawk HPS pads and Wilwood linesets for a 240SX (Wilwood kits do not come with these). I can substitute in other Hawk pads for relative dealer cost differential. I recommend DTC-60s for track usage.

    KIT INFO:

    The design goal for the hat was a semi-floating design(the best possible with the Wilwood rotors - they cannot be fully floating in the space available). With this in mind, I have allowed for a radial slot where the rotor mounts to the hat that is equal to the thermal expansion between the two materials(iron and aluminum) at a plus or minus 1000 deg F delta. Therefore, the rotor and hat should be able to freely expand and contract at their different material-defined rates with minimal binding. This should keep the rotor from wanting to grow into a "cone" shape that the Wilwood hats force due to being solidly held on one side(threaded into the hats). The hat design keeps the cross sectional area high at all stress paths, yet uses a minimal amount of material. The total weight of the hat is 1.53 lbs, and the rotational inertia is about 40% less than the typical "flat cup" Wilwood rotor hat.

    The hardware kit uses mechanically deformed mil-spec lock nuts, as well as spring washers to maintain tension.

    The caliper bracket is made from 2024-T3 aluminum alloy, which has exceptional fatigue resistance as well as hardness and yield strength approaching that of mild steels and surpassing that of most grades of cast iron. This is a true structural "aircraft" alloy of aluminum, and is exactly what most bulkheads are made of in modern aircraft. The large cross sectional section enables a very stiff and strong bracket, and the usage of aluminum keeps the weight below 0.3 lbs.

    ...and don't worry, it's all been scienced:





    Don't worry about the distorted looking bracket - CATIA magnifies things around 1000x to make displacement visible. This FEA run was a rough assumption of Superman-style S chassis performance and its effect on the bracket. The loading assumption was all braking on the front wheels with 25" tires and total braking decelleration of a 3000 lb S-chassis at 1.5 G's. That would put actual real world braking in the ~1.8-2G range for this loading case. Max loads are around 8 ksi, which is a reasonable level for long term fatigue life without unncessary bulk(there isn't much room for a larger bracket honestly). So you should be able to pull ~2 G's under braking about 10-100 million times without worry. I just want to actually see one of you guys pull that much braking force somewhere.

    Total displacement at the lug mounting holes is about 0.0015" at this braking, so very low. The stock spindle is going to be deflecting more than that I suspect.

    The FEA analysis did bring about a few design minor design changes, so they're not just pretty pictures.

    Pushing it beyond the S-chassis aftermarket "well it works I guess" phase, kids!


    Prototype Pics:



    Brackets are made from 2024-T3 "aircraft aluminum" - this is the same stuff they use to make bulkheads and brackets in aircraft due to its high strength and fatigue resistance. Hats are 6061-T6 to keep the cost reasonable.






    The rotors will be held to the hat with Grade 8 bolts, high temperature spring washers(belleville washers), and military spec "jet nuts." These are high temperature, vibration resistant nuts used on military aircraft. They're also the same nuts PFC uses on all their brake kits.



    Back side



    If you want to add Speedbleeders to your Wilwood FSL calipers - here's the Russell p/n(it/s a 1/4-28 bleeder). So now you know, and knowing is half the battle.


    "So how's it all look Def?" you ask - budget baller of course!




    But does it all fit well? You bet!



    Pistons are fully retracted on both sides. As you can see - fitment is perfect.


    Bracket looks budget baller:





    GB run will have both the hat and bracket hard anodized a gunmetal grey.









    Installation Instructions








    It looks like I'll need around 6 people to offer the kit at the same price. I know a few people have recently messaged me about it, so I'll try to get the word out.

    GB 5 List:

    1. voiddweller
    2. NCSU.Ben
    3. wawazat
    4. enerj
    5. popz
    6.
    7.
    8.
    9.
    10.
    Last edited by Def; 03-12-2015, 06:01 AM.
    '18 Chevrolet Volt - Electric fun hatch for DD duty!


    DefSport Koni Sleeve and Spring Perch Buy!!!
    http://www.nissanroadracing.com/showthread.php?t=5902

  • #2
    You able to do a spare set of hats/brackets? I already have a kit and would like to have spare AL parts just in case something happens, etc. Also depends on timing too, don't have the funds right this second, but if I'm able to jump in before the end, I definitely want to grab the spares if that's possible.

    www.2LiterTurbo.com (Personal Site)
    96 240SX SE: Track Car | 90 Skyline GTR: Bucket List Car | 07 Legacy Spec B: The DD

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    • #3
      How many times can I re-use the jet-nuts on the rotor hats? Is that something that I should consider replacing based on a given service life like after X number of rotor changes?
      '95 240sx

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      • #4
        Perfect Def, count me in.

        *edited to get old GB info out of this GB.
        Last edited by enerj; 03-03-2015, 12:29 AM.

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        • #5
          That GB was 2 years ago, so my Wilwood component cost has gone up about 12-15% since then...

          I'll update the first post with pricing if we hit 6 people.
          '18 Chevrolet Volt - Electric fun hatch for DD duty!


          DefSport Koni Sleeve and Spring Perch Buy!!!
          http://www.nissanroadracing.com/showthread.php?t=5902

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          • #6
            Pricing is up top in original post. Decided to stick with Hawk pads for now, so price went up $10 from last GB, as Wilwood charged me something insane like $140 to ship 3 25 lb boxes to me last time. I think the HPS is generally a slightly better street pad than a BP-10 from what I read (haven't run street pads in a long time personally).
            '18 Chevrolet Volt - Electric fun hatch for DD duty!


            DefSport Koni Sleeve and Spring Perch Buy!!!
            http://www.nissanroadracing.com/showthread.php?t=5902

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            • #7
              Original post link is not there.

              Was looking to see if it includes the adapter for the caliper to hose. Highly recommend a 90* fitting. I ended up with a straight fitting that worked but changing to the 90 made everything much happier.

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              • #8
                Originally posted by 2_Liter_Turbo View Post
                You able to do a spare set of hats/brackets? I already have a kit and would like to have spare AL parts just in case something happens, etc. Also depends on timing too, don't have the funds right this second, but if I'm able to jump in before the end, I definitely want to grab the spares if that's possible.
                Sure, you can contact me offline for this when you're ready.

                Originally posted by Sleepy_Steve View Post
                How many times can I re-use the jet-nuts on the rotor hats? Is that something that I should consider replacing based on a given service life like after X number of rotor changes?
                There's not a set number. I've personally reused the same jet nut quite a few times. It's a personal judgement call really.

                Originally posted by jfryjfry View Post
                Original post link is not there.

                Was looking to see if it includes the adapter for the caliper to hose. Highly recommend a 90* fitting. I ended up with a straight fitting that worked but changing to the 90 made everything much happier.
                What link?

                Pricing is at the top of the first post.


                Linesets include adapter fitting, I believe they're straight. You can get other ones if you like. It's 1/8" NPT to -3 AN.
                '18 Chevrolet Volt - Electric fun hatch for DD duty!


                DefSport Koni Sleeve and Spring Perch Buy!!!
                http://www.nissanroadracing.com/showthread.php?t=5902

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                • #9
                  So this is a complete kit including Wildwood calipers less the rotors?

                  Depending on timing I will be in for one, I have a lot out on the engine build at the moment.
                  94 Vert on long road to RR recovery
                  89 Hatch DD(died in crash)
                  96 S14 stock KA/MT DD (replaced 89)

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                  • #10
                    Yes, full kit without rotors. Any 12.12" x 1.25" 8 x 7" through hole rotor will work (Hawk DTC, AP Racing, Wilwood, Coleman etc.).
                    '18 Chevrolet Volt - Electric fun hatch for DD duty!


                    DefSport Koni Sleeve and Spring Perch Buy!!!
                    http://www.nissanroadracing.com/showthread.php?t=5902

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                    • #11
                      12.19" you mean right? That looks to be the common one.

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                      • #12
                        Yea, sorry, mistyped. 12.19" rotors (also commonly called 12.2", which is what I was going for).
                        '18 Chevrolet Volt - Electric fun hatch for DD duty!


                        DefSport Koni Sleeve and Spring Perch Buy!!!
                        http://www.nissanroadracing.com/showthread.php?t=5902

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                        • #13
                          Ever considered using Nord locks?

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                          • #14
                            They will chew into the rotor hat.


                            And why? The jet nuts are cheaper than nord locks + regular nuts.

                            All nice BBKs use jet nuts. There's a reason.
                            '18 Chevrolet Volt - Electric fun hatch for DD duty!


                            DefSport Koni Sleeve and Spring Perch Buy!!!
                            http://www.nissanroadracing.com/showthread.php?t=5902

                            Comment


                            • #15
                              I wonder what those of us running the GKTech aluminum front spindles get into since the caliper bracket bolts on as well. Would it worry you to bolt a caliper adapter onto their aluminum bolt on bracket?

                              It would be nice if I had the coin to send their CAD file to a machinist that could make another set of brackets for this setup, haha.

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