[obert]

I am having a hard time figuring out this rear rotor upgrade.

All I am trying to do is upgrade to a 330x20 drilled stop tech rotor on my base RWD 328i.

I bought a set from a 435 rwd but the inside of the rear rotor is way to big so the e-brake would not work.

https://f30.bimmerpost.com/forums/sh....php?t=1744883

But if I go here it says they are compatible?

https://www.turnermotorsport.com/p-2...5i-435ix-pair/

Why am I having such a hard time figuring this out

i have already bought the wrong stuff and now have to try and sell it. I dont want to order the wrong parts again.

[Gen13 F36]

Bro...You're not gonna like the answer.

Your original rear base brake rotor is 300x20 with 160 mm ebrake

The 330x20 rotor only came with 180mm ebrake.. the ebrake won't work. And there is no 330x20 with the small ebrake

[obert]

Originally Posted by Gen13 F36

Bro...You're not gonna like the answer.

Your original rear base brake rotor is 300x20 with 160 mm ebrake

The 330x20 rotor only came with 180mm ebrake.. the ebrake won't work. And there is no 330x20 with the small ebrake

So everyone that has done this conversion has no ebrake? If this is the case then I should just keep the stuff I bought but want to make sure.

Thanks for the reply

[johnung]

Originally Posted by obert

I am having a hard time figuring out this rear rotor upgrade.

All I am trying to do is upgrade to a 330x20 drilled stop tech rotor on my base RWD 328i.

I bought a set from a 435 rwd but the inside of the rear rotor is way to big so the e-brake would not work.

https://f30.bimmerpost.com/forums/sh....php?t=1744883

But if I go here it says they are compatible?

https://www.turnermotorsport.com/p-2...5i-435ix-pair/

Why am I having such a hard time figuring this out

i have already bought the wrong stuff and now have to try and sell it. I dont want to order the wrong parts again.

Try searching a little more extensively just to make sure that you cannot find a rear 330mm x 20mm (160mm handbrake). I have seen some less popular sized rotors that for whatever reason aren't sold in the US, but are sold in Europe. Obviously they cost more to ship here.

Your other option is to upgrade your rear calipers to the 2-piston Brembo over 345x24. Zimmermann makes one for 160mm handbrake, part# 150.2921.20. I'm not sure if StopTech or Centric makes a rotor that size for 160mm handbrake.

345mm rear calipers require a minimum 18" road wheel.

Front 340mm/Rear 330mm Brake combination will tend to nose dive under heavy braking. But Front 340mm/Rear 345mm combination will squat flat in a much more controlled manner.

[johnung]

Originally Posted by obert

I am having a hard time figuring out this rear rotor upgrade.

All I am trying to do is upgrade to a 330x20 drilled stop tech rotor on my base RWD 328i.

I bought a set from a 435 rwd but the inside of the rear rotor is way to big so the e-brake would not work.

https://f30.bimmerpost.com/forums/sh....php?t=1744883

But if I go here it says they are compatible?

https://www.turnermotorsport.com/p-2...5i-435ix-pair/

Why am I having such a hard time figuring this out

i have already bought the wrong stuff and now have to try and sell it. I dont want to order the wrong parts again.

If anyone is wondering if a car has the 160mm handbrake or the larger 185mm handbrake, please see the photo for an easy lookup by VIN.

The 6-cylinder F3x like 335i/435i and 340i/440i should all have the larger 185mm handbrake

[Onizukachan]

OP: Some cars like xdrives and vert have the larger ebrake, With 300mm rotors as evidenced by the backing plate being too large, but Smaller engine RWD had that small one. Forget if later cars all went to larger rear ebrake but real OEM can probably confirm that.

Forgot where I read it, but Someone had the Big ebrake rotors sleeved with an inner ring to size them down for the smaller ebrake... I’m sure to pass MOT or similar. That might also be a solution for you.

Dunno how feasible it would be to convert from small to larger ebrake. Since it didn’t affect me I didn’t delve to deeply into it.

[Onizukachan]

Sorry for delay, found where I read about the inner 12 mm thick sleeve to size the big rotors down.

https://f30.bimmerpost.com/forums/sh....php?t=1004809

[sqwinny]

Originally Posted by obert

I am having a hard time figuring out this rear rotor upgrade.

All I am trying to do is upgrade to a 330x20 drilled stop tech rotor on my base RWD 328i.

I bought a set from a 435 rwd but the inside of the rear rotor is way to big so the e-brake would not work.

https://f30.bimmerpost.com/forums/sh....php?t=1744883

But if I go here it says they are compatible?

https://www.turnermotorsport.com/p-2...5i-435ix-pair/

Why am I having such a hard time figuring this out

i have already bought the wrong stuff and now have to try and sell it. I dont want to order the wrong parts again.

make sure you look at the 330mm rotors here. They will fit with your E brake and you dont have to make modifications. this is what I used to do the same conversion you are in the process of doing now:

https://www.ecstuning.com/BMW-F30-32...g/Rotors/Rear/

choose a part number and buy from whatever vendor you choose.

I use these in 345mm and have no complaints I bought from amazon (free prime shipping and if they didnt fit i could always put them back into the box and ship at no cost at a UPS store) (2013 328i 6MT F30 sedan):

https://www.ecstuning.com/b-power-st...br1414xpr~pst/

edit: search for 2013 335i base rear rotors (non M sport) and thats the rotor you want. Sometime in 2014 the inside of the rotors change due to the parking brake as well. hope this helps.

[Gen13 F36]

Originally Posted by Onizukachan

Sorry for delay, found where I read about the inner 12 mm thick sleeve to size the big rotors down.

https://f30.bimmerpost.com/forums/sh....php?t=1004809

I read this thread over and over... good to know but not all of us mechanically inclined and handy with tools.

I would suggest just run the 4 piston brembo 340mm with the base stock 300x20 rear brake. I think the bias will not be a problem. I think the piston size of the 330x20 and 300x20 sliding caliper is the same.

[5mall5nail5]

I had originally bought brakes for my '15 328 RWD in accordance to a vendors drop downs. I ordered an M Performance brake kit. When they arrived, I started with the rears and...



You can see original rotor and replacement rotor were much different diameter. It turns out that I think everything built post- 9/14 (its on TIS or RealOEM some place) uses the larger diameter. Whats the build date of your car? So, yes, if you understand me, I have a '15 328 RWD that uses "335" rear rotor hub size... stock.

[obert]

Originally Posted by 5mall5nail5

I had originally bought brakes for my '15 328 RWD in accordance to a vendors drop downs. I ordered an M Performance brake kit. When they arrived, I started with the rears and...



You can see original rotor and replacement rotor were much different diameter. It turns out that I think everything built post- 9/14 (its on TIS or RealOEM some place) uses the larger diameter. Whats the build date of your car? So, yes, if you understand me, I have a '15 328 RWD that uses "335" rear rotor hub size... stock.

Lol it gets even more confusion.

I have a 2013 328 with the smaller e-brake size. The stuff I bought came off a 2014 435 with the bigger e-brake size.

[5mall5nail5]

Originally Posted by obert

Lol it gets even more confusion.

I have a 2013 328 with the smaller e-brake size. The stuff I bought came off a 2014 435 with the bigger e-brake size.

So from my research, which is spotty now, when doing my M Perf upgrade, all 335 are large. All 328 are small.... except after either 4/14 or 9/14 build date, I forget which.

[Onizukachan]

Think it is 7/2014 Brandon.

XDrive and verts and *35 rwd always had the larger carrier and bearing, meaning also larger e brake.

Iirc only 328 and smaller+ rwd + pre 7/2014 have small rear, post 7/14 they are also large.

Yay for confusion!

[obert]

So should I ask StopTech for a rear rotor for a 2013 328 RWD and then one for a 2015 and see if the can tell me the difference e-brake diameter? M sport package?

[obert]

On ECS site some of the rotor options say build date after 7-14 only

[Onizukachan]

Now you know those are big ebrake rotors.

[ottowerke]

Originally Posted by johnung

Try searching a little more extensively just to make sure that you cannot find a rear 330mm x 20mm (160mm handbrake). I have seen some less popular sized rotors that for whatever reason aren't sold in the US, but are sold in Europe. Obviously they cost more to ship here.

Your other option is to upgrade your rear calipers to the 2-piston Brembo over 345x24. Zimmermann makes one for 160mm handbrake, part# 150.2921.20. I'm not sure if StopTech or Centric makes a rotor that size for 160mm handbrake.

345mm rear calipers require a minimum 18" road wheel.

Front 340mm/Rear 330mm Brake combination will tend to nose dive under heavy braking. But Front 340mm/Rear 345mm combination will squat flat in a much more controlled manner.

I have the OEM M performance brakes (370mm front and 345mm rear).
Front is already in.
Planning to install the rear on my e90 328i which I believe has the 160mm shoes.
As you said, the Zimmerman rotors (150.2921.20) is made for the 160mm shoes,
I’m assuming the oem rear rotors I have (Mfg #34206797607) is for 185mm since it is from a f30 335 with m performance brake package.

Now if what I stated above is correct, does 150.2921.20 rotor vs #34206797607 is basically the same (size and fitment) and the only difference is the hat size for the different shoe size?

Thanks in advance!

[johnung]

Originally Posted by ottowerke

I have the OEM M performance brakes (370mm front and 345mm rear).
Front is already in.
Planning to install the rear on my e90 328i which I believe has the 160mm shoes.
As you said, the Zimmerman rotors (150.2921.20) is made for the 160mm shoes,
I’m assuming the oem rear rotors I have (Mfg #34206797607) is for 185mm since it is from a f30 335 with m performance brake package.

Now if what I stated above is correct, does 150.2921.20 rotor vs #34206797607 is basically the same (size and fitment) and the only difference is the hat size for the different shoe size?

Thanks in advance!

I don’t recall E90 and F30 brakes being compatible. Last time I checked for E90 parts they were very different sizes than F30 brakes.

[ottowerke]

I have successfully retrofit the front brembo from F30 to my e90.
Bolt on, no modifications required for the front. The rear however need some modifications.

[E90lova]

Originally Posted by ottowerke

I have successfully retrofit the front brembo from F30 to my e90.
Bolt on, no modifications required for the front. The rear however need some modifications.

So you could buy my F80 M3 front brake upgrade when I decide to upgrade to 6 pot front brakes then yes?

[ottowerke]

Originally Posted by E90lova

So you could buy my F80 M3 front brake upgrade when I decide to upgrade to 6 pot front brakes then yes?

I am pretty sure F80 brakes isn’t bolt on. The front rotor is 380mm, and the caliper won’t bolt on.