Page 1 of 7 1234567 LastLast
Results 1 to 25 of 163

Thread: Bored Bleedsblue: "budget" minded Brembo BBK

  1. #1
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans

    Bored Bleedsblue: "budget" minded Brembo BBK

    2020 Edit: Also removed chaff related to the abandoned 996 setup, and linked our current Brembo brake option
    I've left a lot of the thread intact for future use if folks would like to experiment, we like to foster that!

    While buying new can total ~$1500, our best-selling F30-based BBK can be done on a serious budget by sourcing used calipers, which are many times $400-600 a pair on eBay and via other sources.

    https://www.angryasssolutions.com/parts/stage-1-bbk

    Funny enough, while we didn't end up using the E46 M3 front rotors, we are in the midst of developing an E46 M3-based rear axle kit, to mirror the very late E34 M5 328x20mm kit. The E46 offers a 42 or 48mm piston for tuning options; late M5 was only 40mm.
    Last edited by BleedsBlue; 09-25-2020 at 02:44 PM.
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  2. #2
    Join Date
    Jun 2017
    Location
    Chicago
    Posts
    295
    My Cars
    1995 540i & 1996 328i
    First of all thank you for your time and energy, writing up a wonderful post like this!

    Correct me if I'm wrong but doesn't the 540i have more front brake bias than the m5? Just curious how this will change the brake feel

    My brakes are on the list of near repairs and I'm excited to see an affordable option... I'm very interested and will be doing some research as well.

    Prior to this thread I was considering ceika...
    Last edited by Billyj; 07-21-2017 at 10:19 PM.

  3. #3
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    You can thank my insomnia lately. This first time home buying business is terrifying. Haha.

    According to internet sources (of fairly good repute), here are some typical brake bias setups:
    • Stock 540i: 69/31
    • Stock M5 pre-5/94: 70/30
    • E31 Brembo front, 540/M5 rear: 65/35
    • Post-5/94 M5: 66/34


    An engineer friend did some calculations, and bounced it off some other nerds, and believes adding just the 996 front will increase front bias by 10% over the stock pre-5/94 M5. That's not ideal, but most E36 guys do use four Brembos all around. He thought an aggressive rear pad on a 540/M5 stock rear would get things at least close to stock bias. For guys looking for the ultimate edge, a matching rear Brembo kit would be ideal (though so would adjustable brake bias, etc etc etc) but I haven't started looking at the Rally Road rear axle kit, since E34 and E36 rear axles are super different.

    A nice bonus is the 996 master cylinder is 25mm, same as the E34 M5.
    Also reconsidering ponying up the extra $200 for semi-floating 325x28s, since they are about 8lbs lighter per corner

    Good questions, Billy!
    Last edited by BleedsBlue; 07-22-2017 at 12:44 AM.
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  4. #4
    Join Date
    Jun 2017
    Location
    Chicago
    Posts
    295
    My Cars
    1995 540i & 1996 328i
    Any idea on the caliper bore ? You mentioned a 10% increase in bias, what's break setup is your baseline reference?

  5. #5
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    Quote Originally Posted by Billyj View Post
    Any idea on the caliper bore ? You mentioned a 10% increase in bias, what's break setup is your baseline reference?
    Whoops--I'll update the post, I meant 10% more front-biased compared to a stock E36 M3 or E34 M5 pre-5/94. There is some debate about this, but I trust this engineer.

    The piston bores are 40mm and 36mm (x2).
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  6. #6
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    Yeah I'll be going floating. Jiminy Christmas, this is sexy:

    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  7. #7
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    Interesting pad dimension comparison here:


    Obviously, you've got four pistons instead of one, and more rotor area for heat dissipation; just wanted to post every bit of info I can find.
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  8. #8
    Join Date
    Jun 2017
    Location
    Chicago
    Posts
    295
    My Cars
    1995 540i & 1996 328i
    Pad dimensions are very close, slightly more area on the porsche, should help it last a bit longer.
    I was more curious about the hydraulic ratio between the master and calipers.

  9. #9
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    The E36 and E34 Ms both use a 25mm master; so does the 996. One of the more noticeable advantages to this swap that E36 guys praise is improved pedal feel.
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  10. #10
    Join Date
    Sep 2005
    Location
    Canada
    Posts
    1,252
    My Cars
    E30 M3, E34 M5, E36 M3

    Thumbs up

    You've pretty much made the case for the E31 big brake upgrade. Why bother with the hassle of the Porsche calipers when the E31 parts are already perfect?

  11. #11
    Join Date
    Jun 2017
    Location
    Chicago
    Posts
    295
    My Cars
    1995 540i & 1996 328i
    Shockwave I'm super jealous of your cars !

  12. #12
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    Quote Originally Posted by Billyj View Post
    Shockwave I'm super jealous of your cars !
    Doooooooood, don't get me started. Paul's fleet and BMW-obsessed wife are legendary. She has build threads!

    Quote Originally Posted by Shock(/\)ave View Post
    You've pretty much made the case for the E31 big brake upgrade. Why bother with the hassle of the Porsche calipers when the E31 parts are already perfect?
    Yeah... yeah. I realized that more than halfway through thinking and researching this. I know I regurgitated a load of text, but the only real advantages of this over the E31 are:
    • Weight (w/ floating rotors...consensus is out on E31 Brembo vs 996 Brembo caliper wt diff)
    • Floating rotors (nix this if you can get E31s as floaters)
    • Parts availability could be better, at least the calipers (rotors and pads are a wash)
    • Cost


    E31 Brembos have been sold for a wide range of prices, from $350/pair to $800/pair, whereas 996 calipers are typically under $350/pair. And E31s have been sighted less frequently as of late.

    Particularly if you want new parts, though, I would just buy new E31 Brembos while you still can. You can't deny the bolt-on OEM mod.

    I've also gone down a rabbit hole recently trying to figure out if these have more or less brake torque than the stock 3.6 M5 single piston. It's confusatory, but then again, I'm no engineer. I'm now doubting the engineer I thought I trusted and thinking these calipers have less brake torque than a stock M5 front.
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  13. #13
    Join Date
    Sep 2005
    Location
    Canada
    Posts
    1,252
    My Cars
    E30 M3, E34 M5, E36 M3

    Arrow

    Quote Originally Posted by Billyj View Post
    Shockwave I'm super jealous of your cars !
    If it makes you feel better, the E30 M3 is in the middle of a maintenance overhaul and isn't running, the E34 M5 just developed a battery charging problem and is parked until it's fixed, and the E36 M3 is in the middle of an exhaust replacement and is parked until that's done... so the only cars I have that are road worthy are my E30 325ix (which has a leak and needs fluid changes in the differentials to keep them in top shape) and E28 528e (which we're still finishing the interior swap in and is in urgent need of brakes on all four corners and is leaking oil from somewhere).

    Sounds awesome, doesn't it?

    Quote Originally Posted by BleedsBlue View Post
    Doooooooood, don't get me started. Paul's fleet and BMW-obsessed wife are legendary. She has build threads!
    She's a keeper for sure. She's even started organizing meets.

    Quote Originally Posted by BleedsBlue View Post
    Yeah... yeah. I realized that more than halfway through thinking and researching this. I know I regurgitated a load of text, but the only real advantages of this over the E31 are:
    • Weight (w/ floating rotors...consensus is out on E31 Brembo vs 996 Brembo caliper wt diff)
    • Floating rotors (nix this if you can get E31s as floaters)
    • Parts availability could be better, at least the calipers (rotors and pads are a wash)
    • Cost


    E31 Brembos have been sold for a wide range of prices, from $350/pair to $800/pair, whereas 996 calipers are typically under $350/pair. And E31s have been sighted less frequently as of late.

    Particularly if you want new parts, though, I would just buy new E31 Brembos while you still can. You can't deny the bolt-on OEM mod.

    I've also gone down a rabbit hole recently trying to figure out if these have more or less brake torque than the stock 3.6 M5 single piston. It's confusatory, but then again, I'm no engineer. I'm now doubting the engineer I thought I trusted and thinking these calipers have less brake torque than a stock M5 front.
    Parts availability isn't an issue if they can still be bought new. Were I seriously looking into this I would invest some time into looking for floating rotors which fit on the E31 calipers. Post a thread in the E31 forum here and see what they can tell you.

  14. #14
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    Quote Originally Posted by Shock(/\)ave View Post
    If it makes you feel better, the E30 M3 is in the middle of a maintenance overhaul and isn't running, the E34 M5 just developed a battery charging problem and is parked until it's fixed, and the E36 M3 is in the middle of an exhaust replacement and is parked until that's done... so the only cars I have that are road worthy are my E30 325ix (which has a leak and needs fluid changes in the differentials to keep them in top shape) and E28 528e (which we're still finishing the interior swap in and is in urgent need of brakes on all four corners and is leaking oil from somewhere).

    Sounds awesome, doesn't it?

    Parts availability isn't an issue if they can still be bought new. Were I seriously looking into this I would invest some time into looking for floating rotors which fit on the E31 calipers. Post a thread in the E31 forum here and see what they can tell you.
    Hey man, you can still pop open a tall, cold one and sit in a chair and admire the (broken) fleet with pride

    Re: E31 availability. I agree, I can't call the parts hard to find when they are available online from a variety of sources (though I don't profess to know the stock left at BMW NA, of course). But bought new, a pair of E31 Brembos are $1150 from ECS, as an example. With just blank rotors and good pads, you're nearing $1500. I have verified there are no readily-available floaters for that rotor size, unfortunately (at least that are public knowledge).

    Not to debate the merit of buying new calipers vs easily rebuilding used calipers (I'm a fan of used, since calipers are almost infinitely rebuild-able), but I think I would prefer a lightly used 996 set-up with the floating Euro E46 M3 325mm rotors to a new E31 set-up. When buying the E31 calipers new, compared to used 996 calipers, the entire cost of the 996 BBK should be about $200-300 less depending on options.

    The 996 set-up will be lighter (mainly in the rotors, again only if using Euro 325mm floaters), est. 7-8# lighter per corner. The E31 Brembos and 324x30mm rotor is only ~0.5# lighter per corner than stock M5 pre-5/94. With brackets, the 996 calipers will weigh close to what E31 Brembos do, about 8# each.

    Brake bias should be similar assuming stock rear 540i/M5 pre-5/94; in both cases, bias should shift REARwards (desirable for most) according to most sources. Also the 25mm stock M5 pre-5/94 master cylinder should be a good fit for either E31 or 996 Brembos.

    Caveat
    I will update the first post, but it's become clear that the "margins" on this BBK come with some caveats, compared to the tried-and-true, bolt on E31 Brembo set-up. If "my" kit works (there are multiple threads across forums of others considering this), it will basically only be worth it if:
    • You are interested in 7-8# unsprung mass reduction per front corner (and either capable of milling a caliper mount, or paying $95 for Rally Road to do it perfectly)
    • You want a bigger rotor, with the available 348mm E46 CSL/ZCP floater (though weight reduction almost disappears with the increased thermal capacity), which doesn't require caliper milling but likely needs 18s
    • You don't want to pony up for $1150 of new E31 Brembos, and don't want to wait to jump on a used set (likely still more $ than 996 calipers)
    • You are capable of drilling two easy holes in the rotor hat/paying a shop to do so


    I will likely hold off on more research until I can actually get the parts on hand for wheel fitment. According to some old threads, I don't think wheel fitment will be an issue honestly, but I will not say a peep until I verify fitment personally, and can provide clearance pictures.
    Last edited by BleedsBlue; 07-24-2017 at 02:11 PM.
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  15. #15
    Join Date
    Jun 2013
    Location
    Southern California
    Posts
    513
    My Cars
    1995 540/6 Calypsorot
    I have the e31 4 piston Brembos and the only downside is increased brake pedal travel before any engagement. Not sure of a possible solution at this point...

  16. #16
    Join Date
    Sep 2005
    Location
    Canada
    Posts
    1,252
    My Cars
    E30 M3, E34 M5, E36 M3
    Quote Originally Posted by UnrulyGrace View Post
    I have the e31 4 piston Brembos and the only downside is increased brake pedal travel before any engagement. Not sure of a possible solution at this point...
    Once there is engagement, is the engagement still linear and the feel uncompromised?

  17. #17
    Join Date
    Jun 2013
    Location
    Southern California
    Posts
    513
    My Cars
    1995 540/6 Calypsorot
    Quote Originally Posted by Shock(/\)ave View Post
    Once there is engagement, is the engagement still linear and the feel uncompromised?
    Absolutely. Linear engagement, great bite and feel. Much better than stock in those areas.

  18. #18
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    Good note to raise, G. This is a common experience with the E36 M3 guys using the 996 set-up, as well. Some have tried to rectify (to little avail), others just chalk it up to more pistons requiring more hydraulic pressure. Most 911s (I haven't driven a later 997 or 991) have a stiff brake pedal, FWIW.
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  19. #19
    Join Date
    Jul 2009
    Location
    CT
    Posts
    4,889
    My Cars
    '94 530iT LSx/T56
    Hey BleedsBlue,
    I have a point to make from my experience than may be helpful. I just want to put a disclaimer out there that I read your post twice making sure I didnt miss the point i am about to make, and didnt see it. If i am blind, i apologize.

    When it comes to the differences between say, the e36 and the e34 front brakes, dont forget the relationship between the surface of the wheel bearing that the rotor sits on, and the brake carrier/caliper tabs on the spindle. This distance is much larger on the e34, hence the deep top hat compared to the e36 car. You need to factor this into the adaptation of the calipers/carriers between spindles. Their relationship, combined with the rotor hat to surface relationship, needs to match that of where the caliper wants to sit when bolted up.

    Hope that makes sense. My experience is not terribly extensive, but i will explain. I, on a whim, bought a non-m e36 Brembo BBK off craiglist many years ago. Replacing my factory 530i touring front brakes, miraculously, the brakes bolted right up, but i have to flip the adapter bracket to the opposite side of the spindle mount tabs. Worked fine until i tore the car apart to adapt e36-like control arms/strut tubes/spindles to my car. I needed rotor replacements, but did not have the deep pockets for replacement BBK-specific Brembo rotors ($250+ EACH). So i did the next best thing, and i went on Centric's website, which allows you to look at rotor dimensions, and found the next best thing, e46 M3 rotors. Shared diameter and rotor thickness with my BBK, just wasnt sure on tophat offset. Took a chance and made out pretty well. Had to have the adapters machined to agree with the new rotor offset, but it all bolted together nicely. I essentially adapted Brembo f40/esprit (not sure which) calipers onto an e36 using an e46 m3 rotor.
    -Alex

  20. #20
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    I really appreciate the input and close read, Alex. This is EXACTLY why I wanted to start a thread months before I committed to this test, since I knew I would get lots of valuable input.

    But, sheesh: I think you exposed the largest potential weakness here, haha. I'm glad!

    I was more caught up in how far outboard the rotor would be, forgetting that there are crucial depth differences between wheel bearings under the rotor. In other words, as Alex points out, screw the rotor hat depth; the E34 bearing depth (say between where the rotor hat sits, and the brake shield + spindle) is deep enough that there is no way a caliper adapter for an E36 will line the caliper up with an E36/46 rotor on an E34 hub. The caliper will be too far inboard, the rotor too far outboard.

    This begs the question, of course, if E36 M3 calipers work (flipped) on an E34 with E34-specific rotors. Or not really begs, since half of point of this kit idea was the off-the-shelf nature, and the other half was better rotor choices (larger + floating). LOL. I would rather investigate bracket modifications than stick with heavy, non-floating E34-fitment rotors, but I know my margins and the value of this are already skin tight when an E31 set-up exists.

    Also, Alex: I can't BELIEVE that E36 BBK bolted up for you just by moving the brackets inboard of the carrier. Was that not the ultimate sigh of relief moment?
    I had a gorgeous silver pair of Lotus calipers (they are visually different from F40s, and not as good IMHO) I thought about adapting for my M5, but then decided to wait for Greg's pair of used F50s due to how slim they are, and the bigger piston sizes. You're saying you had the brackets machined, I assume from scratch/had offset added, correct?

    Seems in this case the only solution would be more material on the brackets to push the caliper further out, if using E46 rotors.

    I will update the thread to detail this other, bigger uncertainty (appreciated again, Alex), but assorted musings:
    • I wonder if the Rally Road kit + 996 calipers might get close if using an E31 rotor...
    • In which case, I wonder if the same kit for the 348 CSL rotor might have a chance of working with late M5 floaters
    • Both scenarios are not that useful; the E31 rotor saves no weight and adds an adapter to the equation, while the late M5 rotors will have unused rotor rings at the center (like the F50s)
    • I am curious if Greg's F50 brackets will bolt up to the 996 calipers, since many Brembos have identical mounting locations. The Lotus calipers would have bolted to Greg's F50 brackets, if the bracket had a tiny bit less material between mounting holes, for instance
    • Either way, I might be able to convince Greg to adapt his bracket design for the shallow E46-based rotor (hope is not lost)
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  21. #21
    Join Date
    Jun 2017
    Location
    Chicago
    Posts
    295
    My Cars
    1995 540i & 1996 328i
    So with floating rotors you can save 14+ of unsprung/rotational weight. That alone is worth the money in my book. And you get some upgraded brakes for free !

  22. #22
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    ^That's certainly where I'm at, Billy. The endeavor is still worth it with my proximity to Greg, I think. We'll see how close his Brembo F50 caliper brackets are to 996 Brembos, and then it'll be a matter of adjusting his well-engineered design to the E46 rotor offset. I still think it's a doable set-up for near $1k that can shave 14-16# of unsprung, plus added thermal efficiency of floating rotors.

    Keep the input coming!!! Ok back to work, I'm behind now
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  23. #23
    Join Date
    Jun 2017
    Location
    Chicago
    Posts
    295
    My Cars
    1995 540i & 1996 328i
    Quote Originally Posted by BleedsBlue View Post
    The E36 and E34 Ms both use a 25mm master; so does the 996. One of the more noticeable advantages to this swap that E36 guys praise is improved pedal feel.
    I was curious do most of the e34s have 23.8mm master bore? What is the 540i bore 25mm?

    Ok all e34s have 25mm masters I believe. The slightly smaller bore is on the e28/e24
    Last edited by Billyj; 07-26-2017 at 12:25 AM.

  24. #24
    Join Date
    Jan 2009
    Location
    ATX
    Posts
    3,450
    My Cars
    Sundry old Grrrrmans
    ^Yeah, I don't actually know. If you researched though, we'll call it good.

    I made a lower offer on a pair of 425/6 calipers from a respected Porsche shop, and...accidentally bought a pair of black calipers. So, here goes! I will likely not be able to test much until I return from an out-of-country trip 8/20, but a deal is a deal.
    - Brent
    www.angry-ass.com

    Quote Originally Posted by danespann View Post
    Every E34 needs the same things in the end.

  25. #25
    Join Date
    Nov 2007
    Location
    Vancouver, Wa
    Posts
    792
    My Cars
    87vert & 24V sedan,98 M3
    I have been seeing people making brackets to put 135i brembos on E36s. Could you put those over a E39 M5 rotor or something? The euro rotor looks like it has the lighter hub like the N'ring brakes.

Page 1 of 7 1234567 LastLast

Similar Threads

  1. BBS RGR and Brembo BBK...
    By JQP-M3 in forum 2001 - 2006 M3 (E46)
    Replies: 16
    Last Post: 04-29-2003, 09:05 PM
  2. Brembo BBK!
    By ///M3 CRAZY in forum Group Purchases & Supporting Vendor Specials presented by eBay
    Replies: 3
    Last Post: 11-20-2002, 05:10 AM
  3. BRAND NEW 12.6" Brembo BBK FOR SALE!! E36/E46
    By Amir in forum BMW Parts For Sale
    Replies: 27
    Last Post: 11-17-2002, 04:18 PM
  4. "POLL" of possible new Categories
    By Bob ///M3 in forum Forum Software Questions & Suggestions
    Replies: 0
    Last Post: 02-27-2001, 07:53 PM
  5. "Poll" of possible new categories!
    By Bob ///M3 in forum Forum Software Questions & Suggestions
    Replies: 0
    Last Post: 02-27-2001, 07:44 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •