E46 M3 Floating Discs..... But not from BMW

[Tommo Two]

Getting annoyed with the BMW 2 piece floating discs that, aren't actually 2 piece, well you cant replace just the rotors.

What have people upgraded to that are true 2 piece floating discs, that enables the replacement of the rotor whilst retaining the bell? In a standard size, i should add?

[AW10]

I'll venture a guess that if someone makes a genuine 2 piece disc compatible with the standard calipers it's likely to cost appreciably more than a standard BMW disc and even the rotor alone would cost more than a standard BMW disc due to the limited market. Most upgrades use bigger discs and calipers at the same time.

[helix402]

https://www.ecstuning.com/BMW-E46-M3-S54_3.2L/Brak...

[PHCorvette]

They are floating 2 piece if they are OEM. I just had to buy a full set for the m5 (same discs just not groved/drilled). If you are looking for price, go and call Cotswold BMW (Gloucester) as they do fantastic prices on M parts. Got mine for less than half what Dick Lovett asked for.

As for aftermarket, Stoptek do a set of replacement discs but you never get to replace just the rotor parts these days. On some AP set ups you can reuse the bell and just have someone what some discs to them but there you go.

[darreni]

AW10 said:

I'll venture a guess that if someone makes a genuine 2 piece disc compatible with the standard calipers it's likely to cost appreciably more than a standard BMW disc and even the rotor alone would cost more than a standard BMW disc due to the limited market. Most upgrades use bigger discs and calipers at the same time.

This.
The BMW discs are of high quality & well priced imho.
Aftermarket 2 piece will be far more expensive and not generally as good quality.

[thebraketester]

helix402 said:

https://www.ecstuning.com/BMW-E46-M3-S54_3.2L/Brak...

They are 2 piece but not floating... best avoiding those.

[Tommo Two]

AW10 said:

I'll venture a guess that if someone makes a genuine 2 piece disc compatible with the standard calipers it's likely to cost appreciably more than a standard BMW disc and even the rotor alone would cost more than a standard BMW disc due to the limited market. Most upgrades use bigger discs and calipers at the same time.

The car it on is an E36 328, 4 pot AP calipers and E46 M3 disc, so yes most upgrades do ;-)

And that is the problem i'm finding all the aftermarket 2 piece floating discs for an E46 M3 are bigger than standard sizes.

The only ones i've found that are the same size are Performance Friction Direce Drive V2s (currently obsolete) and superceeded by the V3s which when I tried to order them, were on a long lead time because they are still making them, and thats no good when I need them for the start of the Race season.

Had a look into those Ess ones but as said they are not floating.

[andyman_2006]

Tommo Two said:

Getting annoyed with the BMW 2 piece floating discs that, aren't actually 2 piece, well you cant replace just the rotors.

What have people upgraded to that are true 2 piece floating discs, that enables the replacement of the rotor whilst retaining the bell? In a standard size, i should add?

---

Hi,

You could try these:

http://www.itectuning.com/bmw-performance-parts/13...

not used them myself (i bought genuine bmw ones front and rear)

But you might want to consider a big brake kit? might get better braking and long term more durable? cant say it would be cheaper though.

Andy

[Tommo Two]

andyman_2006 said:

---

Hi,

You could try these:

http://www.itectuning.com/bmw-performance-parts/13...

not used them myself (i bought genuine bmw ones front and rear)

But you might want to consider a big brake kit? might get better braking and long term more durable? cant say it would be cheaper though.

Andy

See post above yours for aplication.

They look the same as the standard BMW ones Ie floating but pinned, so not fully 2 piece, with replaceable rotors

[andyman_2006]

Tommo Two said:

See post above yours for aplication.

They look the same as the standard BMW ones Ie floating but pinned, so not fully 2 piece, with replaceable rotors

---

Is it worth looking at a full conversion kit?

hispec do some (not sure how good, but costs are far less than AP and Brembo)

http://www.hispecmotorsport.co.uk/335mon.html

and

http://www.hispecmotorsport.co.uk/31028m.html

It would give you the ability to swap rotors alone, and be 2 piece? Various sizes on offer wheel size dependant of course.

With a set of standard E46 BMW discs your looking at nearly £400 anyway makes these kits look good value.

Andy

[thebraketester]

Neither are floating.

[Tommo Two]

I'm using the M3 E46 discs as part of a BBK on my E36 328:

4 Pot AP calipers
E46 M3 Discs
E36 M3 Hubs
Ferodo DS3000 pads


As i use them for racing the discs get abit of a pounding, so hence looking at an upgraded version of the E46 M3 Floating (but pinned) disc, in the standard size.

I'm using race pads, race fluid, race calipers, the only thing not designed for racing is the discs.

I've got plenty of ducting in there aswell.

[AW10]

Perhaps you're braking too much?

[abarber]

There are plenty of caged E46 M3s out there running standard sized performance friction disks and pads. They hold up really well on track and don't grumble as much either.

You can fit the slightly larger CSL/Z4M front disks with their caliper brackets too.

[350 Zed]

Performance Friction Direct do a two-piece floating rotor for the E46 M3. May be worth checking out?

[andyman_2006]

thebraketester said:

Neither are floating.

---

unless running on a track every week, does it really matter? if the OP is running e36 328, why would you need anything more - just curious?

If braking performance is such an big issue then go Full big brake kit..and fit bigger wheels..

I have had no issues with the factory e46 bmw setup on my M3, just using better quality pads than standard, if i were to change would prob fit an AP or Brembo BB kit, but dont feel its worth the costs, at least not for road and the odd track day.

Andy

[thebraketester]

The OP mentioned he wanted 2 piece floating discs.

[andyman_2006]

Tommo Two said:

I'm using the M3 E46 discs as part of a BBK on my E36 328:

4 Pot AP calipers
E46 M3 Discs
E36 M3 Hubs
Ferodo DS3000 pads


As i use them for racing the discs get abit of a pounding, so hence looking at an upgraded version of the E46 M3 Floating (but pinned) disc, in the standard size.

I'm using race pads, race fluid, race calipers, the only thing not designed for racing is the discs.

I've got plenty of ducting in there aswell.

---

Are you not allowed to run a bigger disc/brake kit? are there race regs stopping you from using say a 6/8 pot Big brake kit? i assume from this your in a race series or something, otherwise you could go bigger disc and callipers? and wheel to accommodate?

is it warping the discs then? regularly? was this the reason your after floating disc to try reduce heat and weight?

I'm just surprised its killing the E46 Disc given the performance of an E36 328, and if your race trimmed it would be stripped out and light..?

very curious.

Andy

[Tommo Two]

The race series I'm in (kumho BMW championship) I have to run a 17" wheel, I haven't tried a bigger brake disc or more pot calipers, not sure if there would be room as it's pretty tight under the wheel atm.

I'm experiencing bad vibration through the steering wheel under braking, develops with heat (only happens towards then end of a session) I initially assumed warped discs but more research has also suggested compound pickup from the pads, however discs are old now n e way and need a new set for the start of the season, hence seeing what upgrades are about.

And yea the car is very light, 1065kgs and I do have plenty of ducting

[PHCorvette]

not in a race series but I had exactly the same issue, only under heat, with my m5. It was a result of wearing tca bushes and as said only when there was some heat (ie first found it with a 4000 ft drop to the side whilst up on an alpine pass, not good).