03-03-2016, 05:34 AM | #1 |
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F2x MP BBK ++ - initial impressions
My brake upgrade completed as follows:-
Calipers
BF - DOT 5.1 Pad break-in ritual as follows to get the disc and pad temperatures high enough to ship pad material evenly to the disc faces:-
The std car's brakes are very good - I think EU spec M135i pads are superb for DD and occasional track work - so the m2/m3/m4 sport pads were a leap of faith. However, although its early days, so far no noise but wow can this thing pull up...pedal feel is definitely improved [I have yet to get the DSC/ABS recoded which I think will soften the pedal a tad] with great initial bite but still progressive and easy to modulate [important to me and I was concerned that I might make the brakes too binary]. BP 461m trial fit Front usual 397's Front Rear
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03-03-2016, 09:48 AM | #2 |
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The most critical factor is to get the brake balance spot on. If you change more in one end of the car than the other, you will increase your stopping distance. A lot of brake "upgrades" end up like that.
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03-03-2016, 09:58 AM | #3 | |
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Quote:
During break-in of pads/discs, the force you feel, that makes you lean forward when braking hard enough w/o activating ABS, is noticeably more for a shorter period of time. Indicates greater power and shorter distance. Don't get me wrong the std m135i brakes are good - the initial comparative impressions are that these take the brakes to the next level.
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Fettled M135i EB AT then AW M2 DCT - both gone but not forgotten:
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03-03-2016, 10:56 AM | #4 |
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The optimum braking happens with the tyres on the limit of locking up, and even the stock brakes can do that. I don't think it is possible to reduce the braking distance. It should however be possible to get rid of more heat than the stock brakes can do, and brake better after several hard stops. Usually the most efficient way to achieve this, is to install air hoses from the front of the car to the brake hubs.
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03-03-2016, 11:32 AM | #5 |
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Well, "optimum braking" occurs for a shorter time and distance based on my current set v std m sport setup.
Bigger disc diameter means vented slots on circumference of discs is moving faster through the air increasing the cooling effect. Extra leverage from large discs means that brake force is increased for same pressure applied.... As far as air ducts, I noticed that LCI M135i doesn't have the open ducts as per Pre LCI so not sure if or how you can remove blanking plates from inner wheelarch liner - as per thread below - works on the LCI cars ? http://www.babybmw.net/forum/viewtop...=ducts#p775132
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03-03-2016, 08:17 PM | #6 |
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I think it is possible to open the air ducts. My previous 2012 116i M-Sport had them open from the factory, while they are closed on my LCI 118i M-Sport (with M-Sport brakes). Maybe I don't need to with only 136 hp! :-)
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03-04-2016, 03:33 AM | #7 |
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Is your LCI 118i 3 cyl ?
How does the engine compare with pre LCI 4 cyl ?
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03-04-2016, 06:07 AM | #8 |
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Update - did a dash from South London to Brighton [south coast UK] to home in SW London last night.
Motorway there and empty, cross-country roads on the return journey. This brake setup is, in a word, immense.
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03-04-2016, 10:02 AM | #9 |
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Yes, that's the one. I haven't run it in yet, but it feels rather similar so far. I prefer the 3 cylinder sound, but it seems to run slightly rougher under 1400 RPM than the four. And it rev matches automagically. Turbo lag is similar or maybe less.
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03-04-2016, 11:46 AM | #10 |
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I'm sorry but (already from the first pictures released) the F20 LCI doesn't seem to have anymore the brake ducts, even on the M135i pictured above. That's one of the most deceiving parts of the BMW vision for the future, I guess the aesthetics primed as well as the cost of the (extensive for a LCI) modifications, who cares any more for "Form follows function" (traditionally associated to the M sport packages) ? Not the almighty marketing department and not the future FWD buyers, that's for sure.
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03-04-2016, 12:23 PM | #11 |
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I opened my brake ducts for my track day in my pre LCI M135i; the brakes coped really well.
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