Bmw 135i brakes (grey brembo's) fitment on bmw 125/128i

[Kizzu]

So I came to a point where i have to change my front rotors and found a great deal on a set of 135i brembo brake kit (not the performance ones). Now question is, will they fit straight on on a 125/128i or Am I going to have a hard time doing custom brackets and all of this stuff?
Thanks in advance

[uberschnell]

Think the fronts are a straight swap

[andrey_gta]

The front is Swap straight.

The rear - you will need to bend your Dust shield/heat shield back. They bolt on 100% but the hand brake doesnt work
Custom brake shoes are needed - see my posts in 128i section - "128i no love / or 128i love thread"
Alternitively e46 m3/e60 hand brakes may be made to work using info from my posts

[Kizzu]

Originally Posted by andrey_gta

The front is Swap straight.

The rear - you will need to bend your Dust shield/heat shield back. They bolt on 100% but the hand brake doesnt work
Custom brake shoes are needed - see my posts in 128i section - "128i no love / or 128i love thread"
Alternitively e46 m3/e60 hand brakes may be made to work using info from my posts

Don't have in mind of swapping the rears for now so that's one less problem.
And regarding front bolting straight on, aren't the disk brakes bigger than my 300mm?

[TheSt|G]

Are you fading your stock brakes?

[Kizzu]

Originally Posted by TheSt|G

Are you fading your stock brakes?

What do you mean by fading my brakes?

[TheSt|G]

Originally Posted by Kizzu

What do you mean by fading my brakes?

Are you overheating the stock brakes as indicated by braking performance that becomes more and more reduced(longer and longer stopping distances)?

[3002 tii]

Originally Posted by TheSt|G

Are you overheating the stock brakes as indicated by braking performance that becomes more and more reduced(longer and longer stopping distances)?

Who doesn't fade stock brakes? If you're not fading, you're not driving. If you're not driving, you're not 1addict. If you're not 1addict, you're not enthusiast. If you're not enthusiast, you're not "because racecar". Therefore because racecar = fading stock brakes.

[Kizzu]

Originally Posted by TheSt|G

Are you overheating the stock brakes as indicated by braking performance that becomes more and more reduced(longer and longer stopping distances)?

actually I have uneven distribution of the disc brake and it's making raspy noises when slowing down slowly and thought that if I am going to replace disc and pads, might aswell replace calipers and was thinking of alternatives that could fit straight on but not spending SO much money on them :/

Originally Posted by 3002 tii

Who doesn't fade stock brakes? If you're not fading, you're not driving. If you're not driving, you're not 1addict. If you're not 1addict, you're not enthusiast. If you're not enthusiast, you're not "because racecar". Therefore because racecar = fading stock brakes.

GIVE THIS MAN A COOKIE!

[TheSt|G]

Originally Posted by 3002 tii

Who doesn't fade stock brakes? If you're not fading, you're not driving. If you're not driving, you're not 1addict. If you're not 1addict, you're not enthusiast. If you're not enthusiast, you're not "because racecar". Therefore because racecar = fading stock brakes.

Snarkiness aside, you are fading on the street? If he isn't(which seems very likely), the 135i front brakes are a significant downgrade thanks to the increase in unsprung weight they would provide.

Originally Posted by Kizzu

actually I have uneven distribution of the disc brake and it's making raspy noises when slowing down slowly and thought that if I am going to replace disc and pads, might aswell replace calipers and was thinking of alternatives that could fit straight on but not spending SO much money on them :/

Well, keep in mind that replacement rotors/pads for the 135i brakes are significantly more than your stock 128i brakes.

[Kizzu]

Originally Posted by TheSt|G

Snarkiness aside, you are fading on the street? If he isn't(which seems very likely), the 135i front brakes are a significant downgrade thanks to the increase in unsprung weight they would provide.



Well, keep in mind that replacement rotors/pads for the 135i brakes are significantly more than your stock 128i brakes.

I never really tracked the car so yes, the brakes mainly wore out by ''street use''
which by that term I mean that I have to decelerate quite often and harshly as my driving style isn't quite the best of economy and safety.
apart from 135i brakes what else is there availble that will fit? will m3 e9x fit?

[TheSt|G]

Originally Posted by Kizzu

I never really tracked the car so yes, the brakes mainly wore out by ''street use''
which by that term I mean that I have to decelerate quite often and harshly as my driving style isn't quite the best of economy and safety.
apart from 135i brakes what else is there availble that will fit? will m3 e9x fit?

Wearing out pads/rotors is not brake fade.

As a heads up, none of these brake calipers(135i or E9x M3) are going to do anything for your street driving aside from make your car ever so slightly heavier/slower with worse handling dynamics, and much more expensive brake maintenance.

[Kizzu]

Originally Posted by TheSt|G

Wearing out pads/rotors is not brake fade.

As a heads up, none of these brake calipers(135i or E9x M3) are going to do anything for your street driving aside from make your car ever so slightly heavier/slower with worse handling dynamics, and much more expensive brake maintenance.

then what is brake fade?

and if your statements are right (which they are because yes it's true that they are heavier) why do they make bmwp brakes?

[3002 tii]

Originally Posted by TheSt|G

Snarkiness aside, you are fading on the street? If he isn't(which seems very likely), the 135i front brakes are a significant downgrade thanks to the increase in unsprung weight they would provide.

God no. Unless you're commute consists of going down a mountain lugging 500lbs of passenger/storage, I don't even see how one can really fade brakes on public roads. You have to be driving like a real d*ckhead to experience fade. At best I've gotten the pedal a little soft on aggressive auto-x. Only real fade has occurred on a road course, 1x at Summit Point, 2x at NJMP.

Originally Posted by Kizzu

then what is brake fade?

and if your statements are right (which they are because yes it's true that they are heavier) why do they make bmwp brakes?

For the same reason they make a performance spoiler, it looks nice and it sells! If you want to alleviate any fade or potential fade, just get better pads and higher temp fluids. And even running race pads on a street car is stupid since they'll never reach optimal temps so they'll bite worse. And those in-between "dual duty" pads are just the worst of both, aggressive but way more brake dust and squeal. Get a good street pad like PFC Z-rated and run Motul 600 and you're good to go. If you want the bling, go for the Performance Brakes.

[TheSt|G]

Originally Posted by Kizzu

then what is brake fade?

and if your statements are right (which they are because yes it's true that they are heavier) why do they make bmwp brakes?

Brake fade is when you repeatedly use the brakes heavily(such as 225km/h to 30km/h) in a short time frame which causes them to overheat. It is when they overheat that you get what is known as "fade" and your stopping distances increase. If your brakes already have the needed heat capacity for your driving(no fade), any size increase over that is only worse for overall vehicle performance.

BMW makes the BMW P brakes to make money. Anyone who needs an upgrade and is serious about getting an effective product gets a proper big brake kit made by companies like Brembo(not the only choice).

[Kizzu]

Originally Posted by 3002 tii

God no. Unless you're commute consists of going down a mountain lugging 500lbs of passenger/storage, I don't even see how one can really fade brakes on public roads. You have to be driving like a real d*ckhead to experience fade. At best I've gotten the pedal a little soft on aggressive auto-x. Only real fade has occurred on a road course, 1x at Summit Point, 2x at NJMP.



For the same reason they make a performance spoiler, it looks nice and it sells! If you want to alleviate any fade or potential fade, just get better pads and higher temp fluids. And even running race pads on a street car is stupid since they'll never reach optimal temps so they'll bite worse. And those in-between "dual duty" pads are just the worst of both, aggressive but way more brake dust and squeal. Get a good street pad like PFC Z-rated and run Motul 600 and you're good to go. If you want the bling, go for the Performance Brakes.

so basically a brake disc and pad replacement will do just fine and will still have a decent performance?

[TheSt|G]

Originally Posted by 3002 tii

God no. Unless you're commute consists of going down a mountain lugging 500lbs of passenger/storage, I don't even see how one can really fade brakes on public roads. You have to be driving like a real d*ckhead to experience fade. At best I've gotten the pedal a little soft on aggressive auto-x. Only real fade has occurred on a road course, 1x at Summit Point, 2x at NJMP.

I did get my rental FIAT 500 to fade significantly on public roads in Italy.
Fortunately engine braking was sufficient to prevent me from going over the side of the cliff. To say they don't GAF about how you drive on the street would be putting it mildly.

[3002 tii]

Originally Posted by Kizzu

so basically a brake disc and pad replacement will do just fine and will still have a decent performance?

I'm still not sure what the issue is. Do you want to address fade or uneven pad wear?

If it's fade, then get better pads and higher temp fluids.

If it's uneven pad wear, just learn to do a proper bed-in after your next brake job and avoid any slotted or drilled rotors. Rears tend to wear unevenly because DSC will apply brakes during slip but again, how often is DSC kicking in during a normal commute?

[Kizzu]

Originally Posted by 3002 tii

I'm still not sure what the issue is. Do you want to address fade or uneven pad wear?

If it's fade, then get better pads and higher temp fluids.

If it's uneven pad wear, just learn to do a proper bed-in after your next brake job and avoid any slotted or drilled rotors. Rears tend to wear unevenly because DSC will apply brakes during slip but again, how often is DSC kicking in during a normal commute?

I want to address as performance wise as I am going to replace my front braking system.

[3002 tii]

Originally Posted by Kizzu

I want to address as performance wise as I am going to replace my front braking system.

What area of performance? Shorter stopping distance? If so then look to tires, not brakes. Resistance to fade? Get pads with higher temp resistance. If you want better initial bite, look at Hawk street pads or a brand known in this regard (although Hawk pads dust like none other).

[andrey_gta]

130i/330/z4 e89 330mm rotors and 130i Caliper carriers may be a more sound plan of upgrade for a 128i/125i than 135i brakes.

I do like my 135i brakes for the aesthetics and the feel they gave me compared to my worn out rotors and pads.

[Kizzu]

Originally Posted by andrey_gta

130i/330/z4 e89 330mm rotors and 130i Caliper carriers may be a more sound plan of upgrade for a 128i/125i than 135i brakes.

I do like my 135i brakes for the aesthetics and the feel they gave me compared to my worn out rotors and pads.

And regarding rotors what's the best brand that I should go for or stock will do? And should i buy 130i calipers too or mine will do?