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    #46
    ...from what I measured, claiming accuracy of more than one significant digit's just
    not what happens in the real world.

    So yes, the theory's good, and that's a good explanation, but it's not that repeatable-
    sometimes it'll pull 50% of the pressure, but the next time (let's say you stab the brake
    in a last of the great late- brakers attempt)
    it'll pull 40%, or 60%.
    I came from a bias- bar car that's dead- nuts stable to a Pro3 car where we can only
    run a hydraulic bias adjuster.
    I had lots of trouble getting the rears under control, because I kept trying to use rear brakes
    as much as I could- and then, I'd get Brevilled- "just a bit more" and end up asswise.
    Eventually, I backed them way off, and went faster...

    t
    now, sometimes I just mess with people. It's more entertaining that way. george graves

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      #47
      Sooo. I've seen this thread for a bit but didn't engage. Why do you want to run abs? And why would you want to run abs after a BB delete? especially when you've changed MC, and are running prop valve?etc?

      Comment


        #48
        Originally posted by TobyB View Post
        ...from what I measured, claiming accuracy of more than one significant digit's just
        not what happens in the real world.

        So yes, the theory's good, and that's a good explanation, but it's not that repeatable-
        sometimes it'll pull 50% of the pressure, but the next time (let's say you stab the brake
        in a last of the great late- brakers attempt)
        it'll pull 40%, or 60%.
        I came from a bias- bar car that's dead- nuts stable to a Pro3 car where we can only
        run a hydraulic bias adjuster.
        I had lots of trouble getting the rears under control, because I kept trying to use rear brakes
        as much as I could- and then, I'd get Brevilled- "just a bit more" and end up asswise.
        Eventually, I backed them way off, and went faster...

        t
        Thanks for the real world feedback! this is good to know
        Originally posted by squidrope View Post
        Sooo. I've seen this thread for a bit but didn't engage. Why do you want to run abs? And why would you want to run abs after a BB delete? especially when you've changed MC, and are running prop valve?etc?
        Well, mostly because I still street drive the car quite a bit and I don't trust people on the road in LA. I'm also not confident in my threshold braking skills. All that said, I've already returned to boosted brakes. And my purpose for the car has changed from a "daily" to a weekend only car, so if I were to do it again now I'd probably take a different approach.
        '89 325i OBD2 S52 BUILD THREAD
        Shadetree30

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          #49
          I’m reviving this old thread.

          For those of you that track your cars, do you have any issues?

          I have a Massive setup with Wilwoods up front and stock rear, both running off of an E32 25mm master cylinder and E21 booster. I’m very happy with this setup, but I’m considering going to ITBs, and this would interfere with my booster. I’m not a big guy, so I don’t have gorilla-legs. [emoji3]. Any recommendations on if it’s worth it and what MC I should use?

          Thanks!


          Sent from my iPhone using Tapatalk
          -Brandon
          '86 325es S50
          '12 VW GTI Autobahn DSG
          '03 540i M-Sport (sold)
          '08 Jeep SRT-8 (sold)

          For sale:
          S50 TMS chip for Schricks

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            #50
            Originally posted by Sh3rpak!ng View Post
            Looks like I never updated after I sorted it all out... I actually returned to boosted brakes. New 944 booster feels really awesome. I was doing far more street driving than I intended, and never really got the strong brakes I wanted, especially for the street. Also I think I misunderstood the function of the bias valve when I initially installed it. It's only useful if you have MORE rear bias than you want, you can cut pressure to the rear to decrease it. At the very least, make sure the oem bias valve is removed.

            If I understand correctly, there are two basic ways to increase rear bias; increasing mechanical advantage. Either decrease the size of the rear MC, or increase the total size of the rear caliper piston surface area.

            That said, with my wilwood front kit, rear oem calipers/disks, and oem 17/22mm MC, bias is not that bad. ~67% front iirc.

            I'm testing out a new setup soon though utilizing a Nissan z32 rear 2 piston caliper and a Toyota ma61 rear vented disc which ought to drop front bias to ~60%.

            Sent from my SM-G920T using Tapatalk
            do you think the massive twin M/C kit booster delete be better for the street?



            or is the force/travel relationship going to be the same (all else equal)
            89 E30 325is Lachs Silber - currently M20B31, M20B33 in the works, stroked to the hilt...

            new build thread http://www.r3vlimited.com/board/showthread.php?t=317505

            Comment


              #51
              Originally posted by Beej '86 325es View Post
              I’m reviving this old thread.

              For those of you that track your cars, do you have any issues?

              I have a Massive setup with Wilwoods up front and stock rear, both running off of an E32 25mm master cylinder and E21 booster. I’m very happy with this setup, but I’m considering going to ITBs, and this would interfere with my booster. I’m not a big guy, so I don’t have gorilla-legs. [emoji3]. Any recommendations on if it’s worth it and what MC I should use?

              Thanks!


              Sent from my iPhone using Tapatalk
              I ran the massive boosterless setup with a 25mm master cylinder and it was very difficult for me to stop the car. I literally used all my leg power and couldn't get them to grab, I found myself coasting into brake zones at the track and had absolutely no confidence. I have the booster back in the car now and it's working well.

              If you go boosterless you need to reduce the size of the MC, that was my mistake. This was a track only car BTW.

              Comment


                #52
                As a very short technical note. If using OEM calipers and swapping the original differential bore MC, I strongly suggest to remove the OEM bias valve which is a pressure limiter. Otherwise the rear brakes will be very lazy on high pedal pressures, putting more than needed work on the front brakes and making the car unstable on hard braking. Here's the (probably) 10 years old graph that show what that valve does.

                1 bar is roughly 15 psi



                You can replace it by an adjustable one. But never put both in line. ;-)

                Brake harder. Go faster. No shit.

                massivebrakes.com

                http://www.facebook.com/pages/Massiv...78417442267056





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