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#1
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E46 BMW M3 Brembo / Rally-Road BBK Install
(Flame Suit On Check) I do not like the single-pot floating brake calipers used on these cars for track driving. Yes, I know, some people use them (with track pads and SRF), and I know some series require them, and I know people get by with them but I also know people that have had major issues ( Flying off turn 1 at SP and hitting the wall, etc) with them including me (I just almost flew off but did not hit a wall). To that end, I decided to go the following route as mentioned in the title. So
First Step: Get some 996 / Caymen S Calipers I got mine from John Ts deer strike 996. This seemed like a good approach because in theory, they had the fluid changed frequently ( was a Tech Inspector and is an Instructor) and I got a complete set from the same car. Then,send them to Rally Road for a bit of machining 5.5mm off the mounting pads to be exact. On go the brackets these are beautiful. Note the mounting studs so that you do not have to Time-Sert the suspension parts after you pull the threads out upon removal (you know who you are). I did have a slight issue with the stock mounting bolts. The shoulder on the bolts bottomed out on the threaded bracket before I could get to the correct torque. A thick washer between the head of the bolt and the suspension mount holes fixed this. I need to find a better set of bolts and remove the washer but this is fine for now. The threads on the RR brackets come right to the edge where-as the stock brakes have a slight reset for the bolt shoulder to go into. Next, on go the rotors. These are 345mm by 28mm rotors used on a ZCP/CSL. In this case, I went with the ECS versions of these rotors. These look to be OEM 2-piece rotors, modified and drilled. I could have gone without the drilling but these are heat-treated, have replaceable friction surfaces, and are pretty. We will see how these hold up. I inserted a screw-driver to check which way the internal vanes were going. It turns out PFC also makes a set of 2-piece rotors that should work. Clearly, when these brackets were designed, the designers put as much meat on them as possible at the point where they are threaded and bolted. WOOPs First Issue. The bottom, inside pins on the brake calipers were making contact with the rotor after the caliper was installed. None of the threads I saw mentioned this, so I filed these down a bit, approximately 1.5mm with a hand file to get clearance. I may need to file a bit more we will see. Others options to considered, if it is a problem, is take the rotors apart and have the faces machined 1mm. The calipers go on easy now. The rears were the same but required no filing but did need the dust shield trimmed. Here, Kitty completes his inspection of the custom DOT approved brake lines (also obtained from RR) and indicated his like by lounging next to them. For some stupid reason, I forgot to take some pics of the completed project without the wheels on but oh well. I used 10mm spacers on the front but 12.5mm spacers would be better for a bit more clearance will change if there is an issue. Please note the beautiful wheels. Wheel Doctors did these in satin graphite. There is not a lot of info on this setup in terms of pads but I have decided on DTC-60 all around as a starting point for track usage. |
#2
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WOOPS how dump of me. This car is hard to take pics of because it reflects the surroundings.
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#3
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Love it. Gotta ask, because I've looked at big brake kits for M3 and they are $$$$$$ - what'd this run you?
Main thing I'd be concerned about is bias. Not sure how the 996 calipers compare to the stock single pots piston-area-wise, but it seems like the 996 calipers would be a lot more front biased.
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Chris M 1985 911 Carrera with a couple cosmetic only mods 2006 E90 330i 1999 E46 328i |
#4
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800 Calipers
500 brackets and hoses 750 disks Pads of your choice As far as front to back bias goes, hmmmm. There is a bias formula/model available on m3forums which allows you to calculate it (I think) but I have not done it. This looks to be very similar to the wildwood kits I have on my other car. Also, I know it will not confuse the BMW ABS. In the end, I plan on using pads to tune if it is an issue. The reports I have seen do not indicate this is a problem. For reference, I looked at the "fast-lap" time threads over there and this pad setup seems to be in line. OG also mentioned this is a viable approach. |
#5
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I was thinking of measuring the diameters of the pistons and determining their ratios and comparing that to stock and the wildwood kit I have and love.
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#6
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Nice write up! BM-orsche!
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Martin 2011 Cayman S (Gone) - Hardtop Blechster 2006 Cayman S (DD) 2016 Mazda CX-5 (Her DD) 2002 Boxster S (Gone) - Ragtop Blechster - Pura Patina! Dorkiphus: I buy it for the articles |
#7
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Thanks NOTTON. Now the real question is S or R? Also "Race Car" or "GTB1 Car" or "GTSX Car" Come on - this is the BMW Thread and no one ever comes over here. I promise I will not tell.
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#8
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Quote:
Remember theses fro a couple of months ago? I like your rotors better. Your calipers need some paint!
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David I hope to arrive to my death, late, in love, and a little drunk! Just because I don't care doesn't mean I don't understand... Homer Simpson "That's what's keeping me out of F1.... Too much mental maturity...." N0tt0n Some cause happiness wherever they go; others whenever they go. CHAOS, PANIC, AND DISORDER my work here is done... Live without pretending, Love without depending, Listen without defending, Speak without offending |
#9
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TR - Agree with the paint. I talked to a Dorki about getting them powder coated and he recommended against that for reasons of heat retention. I will do the paint next time I take the off - I am thinking a nice Cobalt Blue. Yes I remember those from Tech. I do like his wheels.
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#10
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I've also been thinking of doing the 996 brakes since I don't know if I want to pony up for the PFC BBK. Could you elaborate on the issues with the stock calipers you are referring to that would cause runoffs?
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Aaron 1993 964 2004 GT3 2017 M3 |
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