128i Brake Upgrade

[mkeiser]

I'm in the beginning stages of planning to replace pads and rotors on my 128i. The car is still my daily driver but a few autocross events a year, and I'm hoping to hit a track day or two this year but we'll see about that.

I currently run a set of 16" wheels in the winter and stock 17" in the summer. Depending on the brake route, I may be able to change that up to 17" in the winter and 17/18" in the summer. I also have been using ATE 200 brake fluid.

I've researched the usual brake caliper upgrade suggestions... e90 335i fronts / f30 335i fronts and e90 328i rears. But I'm wondering if I can just get by with my stock calipers and upgrade the rotors / pads / fluid to something that is able to hold it's own with more spirited driving events.

So I guess my question to y'all would be if I could get by with something like stock rotors (or upgrade to drilled/slotted?), upgraded pads (hawk yellow, ferodo ds2500?), and upgraded fluid? Or should I just aim for upgrading the calipers and go all-in?

[SKI-R]

IMO….(frame of reference is autocross/occasional daily, no track)…..

Until you’re completely hooked (or if you’re independently wealthy and just looking to spend money), I would simply go to the best pads I could and combine them with good fluid (flushed seasonally or if you ever manage to boil it). No need for special rotors.

For autocross I wholly endorse the G-Loc R6 pad compound, but it is targeted directly at autocross in particular - the ‘cold’ bite is astounding. They do not recommend Street or Track use with it - due to noise/dust for the street and I imagine serious fade with prolonged heat from tracking. If I recall correctly pads were close to $700 CAD for front and rear for E9x calipers, so be prepared.

I find the G-Locs no more dusty than the Porterfield R4S that I used previously, but they are NOISY. PM me if you wanna grab my set of (fronts and rears) slightly used Porterfields to try as an intermediate upgrade step (they ARE a good improvement).

Motul fluid for me - that probably stems from the days I spent on bikes!

Again this is all IMO…..I DO have the full E9x front/rear upgrade and would not do it again for how I’m using the car.

[cerealwars]

How close are you to you-pull junkyards? If you're patient, you should be able to pick four calipers for ~$120.

I did a track day in my manual 128i. By the last session of the day I was cooking the oil (i pitted once I hit ~290) and the front brakes were smoking six laps (~9 minutes) into a 20-minute session. I'm an intermediate driver. If I decided to keep tracking I would add an oil cooler (probably also from a 335i) and do the upgrade you're considering.

[mkeiser]

Originally Posted by SKI-R

IMO….(frame of reference is autocross/occasional daily, no track)…..

Until you’re completely hooked (or if you’re independently wealthy and just looking to spend money), I would simply go to the best pads I could and combine them with good fluid (flushed seasonally or if you ever manage to boil it). No need for special rotors.

This might be the way to go for me. Track days will realistically be few and far between. We have a track 2.5 hrs away but it's a bit intimidating to think about right now Autocross events seem much more approachable and affordable. So it might make the most sense to have a dedicated set of wheels/tires and pads for autocross/track.

Originally Posted by cerealwars

How close are you to you-pull junkyards? If you're patient, you should be able to pick four calipers for ~$120.

I did a track day in my manual 128i. By the last session of the day I was cooking the oil (i pitted once I hit ~290) and the front brakes were smoking six laps (~9 minutes) into a 20-minute session. I'm an intermediate driver. If I decided to keep tracking I would add an oil cooler (probably also from a 335i) and do the upgrade you're considering.

This is good to know, thank you! I do have a junkyard close by that I regularly check inventory for but I've never seen them get a 335i on the lot. I will occasionally check eBay for the calipers as well.

What are you using to monitor oil temp? I've always wanted to toss in a e90 gauge cluster to get that oil temp gauge that some of them have...

[cerealwars]

Originally Posted by mkeiser

What are you using to monitor oil temp? I've always wanted to toss in a e90 gauge cluster to get that oil temp gauge that some of them have...

I have been using bimmergeeks protool with their bluetooth DLC dongle. It was about $200 for the licenses and the dongle, but sooooper worth it already. I can code all kinds of things, I have access to diagnostics and the ability to do most anything a dealership tech could. I just leave the dongle plugged in. As long as I have my phone, I can check just about anything going on with the car at any given time. I just have a vent clip phone mount, and even on track days it holds tight.

The app also lets you create and configure your own gauge setups, displaying any parameters that the DME sees. I have a few setups, some with six gauges (for extraneous things like throttle position, pedal position, O2 readings, etc.). The one I use for track days simply has oil temp on top, and coolant temp on the bottom. It's interesting being able to see how the DME commands the water pump depending on how you are using the car.

I admit it is a little tedious if you want to monitor your temps while daily driving, but since I wanted protool for coding primarily, the gauges are a really handy feature.