[PininMargherita]

Hi, I am considering doing rotors and pads on my F32 with base brakes (312x24mm front and 300x20mm rear). But if I'm able to upgrade to gain stopping for power I'm interested.



I have a few questions:

• Can I upgrade to the 370/340mm in the front without a new dust shield?
• Any other considerations?

Last 7 of VIN: F713031

Considering these calipers: 34116799469, 6799469, 6799470, 6799461, 6799462
Style of driving: City and road trips. No racing; this is more of a touring car.

[PininMargherita]

As I continue my research:

• coding will require a rear upgrade for things to work correctly. So I need 4 new calipers.
• New rear rotors will be 345x24 -
• Leaning towards finding calipers off of a salvaged car and having a local rebuilder paint and refurb the calipers

Open questions:

• Need to confirm the correct "hat" size for my f32's parking brake.
• Will my F32 with base brakes need modification or a new dust shield to accommodate 370/340mm rotors?
• Will my 18" stock wheels clear 370mm?

[johnung]

Originally Posted by PininMargherita

As I continue my research:

coding will require a rear upgrade for things to work correctly. So I need 4 new calipers.
New rear rotors will be 345x24 -
Leaning towards finding calipers off of a salvaged car and having a local rebuilder paint and refurb the calipers


Open questions:

Need to confirm the correct "hat" size for my f32's parking brake.
Will my F32 with base brakes need modification or a new dust shield to accommodate 370/340mm rotors?
Will my 18" stock wheels clear 370mm?

I put your VIN into realoem and your car has the larger 185mm e-brake.

You won’t have to modify anything. I’ll check your dust shield part numbers vs mine. They are easy to swap if necessary.

18” BMW wheels should clear Front 370’s no problem. Some aftermarket 18” have tight cylinder walls that won’t clear.

If used calipers are in good shape, not leaking, with rubber dust shields intact and bleed screws that turn okay, then you shouldn’t need to refurbish with new piston seals, etc.

You can prep & paint yourself with G2USA Caliper Paint. See photo.

[PininMargherita]

Thanks for confirming! Now I've got to source 370mm front calipers

[danb1979]

Originally Posted by PininMargherita

As I continue my research:

• coding will require a rear upgrade for things to work correctly. So I need 4 new calipers.
• New rear rotors will be 345x24 -
• Leaning towards finding calipers off of a salvaged car and having a local rebuilder paint and refurb the calipers

Open questions:

• Need to confirm the correct "hat" size for my f32's parking brake.
• Will my F32 with base brakes need modification or a new dust shield to accommodate 370/340mm rotors?
• Will my 18" stock wheels clear 370mm?

FYI ALL BMW 18" F3x wheels clear the larger 370/345mm brakes - they're what I run on my current F31 with 18" 405Ms as my summer wheels and 18" 397s as my winters

[johnung]

I put your vin into realoem and it appears that you do need to upgrade to larger brake dust shields. Part numbers in photos. I recommend replacing the bolts in that environment too. Great place to get Genuine parts at a discount is the GetBMWParts website. It’s an actual dealer with an online parts group. They know their stuff.

Front dust shield just bolts on. Rear dust shields were installed with the hubs but there is an easy common mechanic’s workaround to cut out a section with tin snips to remove old and install new. It makes the rears bolt-on as well. See photo.

Another source for new brake shields would be anyone who bought a BMW M Performance Brake Kit to upgrade from a stock Front 340mm, Rear 330mm setup. The kit contains all new shields but their car already came from the factory with the same shields. So they are probably just sitting on a shelf in their garage. Put out Want To Buy notices on regional Bimmerpost and Facebook forums to ask if anyone who installed the MP Brake Kit has them laying around and wants to make cash and gain space.

[johnung]

BRAKE PADS
Upgrading from the smallest to largest F3x brake setup will obviously increase stopping power. Brake pads can make a big difference, so choose wisely.

I highly recommend Hawk 5.0 pads for street use. Great bite, instant warm up and low dust. See photo for part numbers. Avoid ceramic which are marketed on low dust feature, but their actual brake performance is no better than average.

ROTOR QUALITY
There are highly marketed brands like PowerStop and R1 Concepts with slick marketing that are actually cheap overseas crap. When they warp, good luck obtaining customer service because that is poor too.

Stick to solid brands with high quality metallurgy like German made Zimmermann, StopTech, Brembo, Paragon.

ROTOR SURFACE
The two best options for street use are plain or full crossdrilled. Avoid anything dimpled or slotted. The dimpled & slotted rotors that come in the BMW Aftermarket M Performance Big Brake Kit are a scam by BMW Marketing. They’ve convinced people that the look cool so they can charge a higher price. Reality is that they offer little actual brake performance improvement and they have numerous noise complaints.

FULL CROSSDRILLED
BMW installs full crossdrilled rotors on the M2/M3/M4 because they have the best bite. And they are the best in rain because water can’t trap between pad and rotor. Many other makes like Porsche, Mercedes, McLaren, etc also install full crossdrilled rotors on their street performance cars.

RACING ONLY BRAKE ROTOR SURFACES
Full blown race car brakes have to deal with incredibly high heat that can’t be produced on the street. To get their rotors to perform under extreme conditions they use plain rotors with various sharp slotted edges, C shapes and others cut into the surface. The idea is that when rotors are glowing red hot that these sharp edges will cut into the pads to prevent them from glazing over, causing brakes to fade. Again absolutely zero advantage on the street, only tears up pads sooner without the bite advantage of full crossdrilled rotors.

GREAT REPLACEMENT ROTORS
German Zimmermann plain rotors are high quality and reasonably priced.

UPGRADE TO PLAIN ROTORS
StopTech full crossdrilled rotors have directional internal vanes for optimal cooling. So they have separate left & right part numbers. See photos for part numbers.

Note: The front brakes do most of the work so it’s not uncommon to have full crossdrilled rotors on the front and plain rotors on the rear. Some of the Mercedes sport models are designed this way. So it’s a way to get the performance of full crossdrilled on the front and save some money by installing plain on the rear. Of course install all four full crossdrilled if you can afford it for maximum brake performance.

ULTIMATE STREET ROTOR
The ultimate street rotor is a full floating, full crossdrilled front rotor. Full floating is a design that came out of racing. It uses a lightweight aluminum top hat that attaches to a solid ring that is the surface that the pad sweeps. The hat and ring are joined by a series of fasteners that allow the ring to “float” to maintain their position as the brakes go through extreme temperature changes. Aluminum and Steel expand and contract at different rates so it’s not ideal to weld or rivet them solidly together. Another benefit of this design is that only the wear ring eventually needs to be replaced.

Note: one photo shows gold coating on rotor. This is rustproof coating. It wears off on pad swept areas and turns black inside holes and vanes to prohibit rust.

Combined with the Hawk 5.0 pads, full floating full crossdrilled rotors have absolutely amazing stopping power.

I have front StopTech full floating 370x30 full crossdrilled rotors that I bought several years ago when they were more reasonably priced. See photo. Now they are approaching $2,500 per pair which is obscene.

Thankfully Paragon Brakes makes a reasonably priced full floating, full crossdrilled 370x30 rotor. Paragon makes the best brake systems for racing the F3x. Many guys who I know who track their F3x’s and M cars have installed Paragon calipers and rotors, instead of the previous brand leader, AP Essex.

Here’s the link for Paragon 370x30 full floating front rotors. The standard configuration is slotted because dedicated trackers are their typical customers. Paragon is very responsive and very easy to work with.

For a small fee they can be custom ordered in full crossdrilled with an added rustproof coating. Total cost is about $1,150 per pair. I know that it still seems expensive but I made a purchase decision because I was able to obtain the technology that BremboGT sells in their almost $5,000 front caliper & rotor kit. That made it a relative bargain. Best performance that could possibly be had from the Brembo 370 calipers.

https://paragonbrakes.com/2-piece-ro...mance-m-sport/

STAINLESS STEEL BRAKE LINES
Make sure to ditch the rubber hoses for stainless steel brakes lines during the installation. Only about $120. Gets rid of sponginess and makes brake pedal firmer. See photo for StopTech part numbers. Also offered by Turner, ECS and Goodridge .

Hope this is helpful!

[PininMargherita]

Awesome, thanks this is super helpful.

Decisions/Confirmations:

• I need to cut and replace the dust shield (Crap). This doesn't look like fun but only needed on 2 wheels.
• My OEM wheels work (yay!)
• Hawk 5.0 pads
• Zimmermann rotors (smooth) 370x30 and 345x24 (larger 185mm e-brake)

Pending:

• I need to cut and replace the dust shield (Crap). This doesn't look like fun but only needed on 2 wheels.
• Still trying to source a pair of 370mm rotors.
• Need to source paint and decals too
• Need to source dust shields
• Do I need larger shields in the front? 34116972081 and 34116872082

[PininMargherita]

Did I get the wrong dust shields?


34-20-8-053-265 Backing Plate
34-20-8-053-266 Backing Plate
34-11-2-284-743 Splash Shield
34-11-2-284-744 Splash Shield

[johnung]

Originally Posted by PininMargherita

Did I get the wrong dust shields?


34-20-8-053-265 Backing Plate
34-20-8-053-266 Backing Plate
34-11-2-284-743 Splash Shield
34-11-2-284-744 Splash Shield

According to realoem with your VIN the front brake dust shields should end in 2081 and 2082. And the rear in 2243 and 2244. Just enter the last 7 of your VIN in realoem, go to brakes, go to photo with dust shield, go to part numbers with dust shields for M Sport S2NHA brakes

[PininMargherita]

Originally Posted by johnung

According to realoem with your VIN the front brake dust shields should end in 2081 and 2082. And the rear in 2243 and 2244. Just enter the last 7 of your VIN in realoem, go to brakes, go to photo with dust shield, go to part numbers with dust shields for M Sport S2NHA brakes

Incredible, your guide makes so much more sense. I have the following:

Dust shields:

• Rear Left: 34216792243
• Rear Right: 34216792244
• Front Left: 34116872081
• Front Right: 34116872082

Also need to order:

• Disc Brake Rotor Set Screw - 34211161806 x 4
• Front: Hex Screw With Collar - Used for brake caliper mounting - 34206850536 - x 4
• Rear: Caliper Hex Bolt - Bolts the caliper to the carrier - 34106864424 - x4
• Rotors
• Pads
• sensor

Ordered:

• Hex Bolt with Washer - Holds the dust shield on - 07119904511 - x 4
• Hex Bolt - Holds the dust shield on - 2nd bolt - 34211164044 - x 4
• Front: Stainless Steel Brake Lines - StopTech - 950.34531
• Rear: Stainless Steel Brake Lines - StopTech - 950.34531
• Brake Dust Shield Bolt - 34116868785 - x 4

Am I missing any other bolts or parts that I should be replacing? Can I use S2NHA part #s for most bolts and parts?

[johnung]

Originally Posted by PininMargherita

Incredible, your guide makes so much more sense. I have the following:

Dust shields:

Rear Left: 34216792243
Rear Right: 34216792244
Front Left: 34116872081
Front Right: 34116872082


Also need to order:

Disc Brake Rotor Set Screw - 34211161806 x 4
Front: Hex Screw With Collar - Used for brake caliper mounting - 34206850536 - x 4
Rear: Caliper Hex Bolt - Bolts the caliper to the carrier - 34106864424 - x4
Rotors
Pads
sensor


Ordered:

Hex Bolt with Washer - Holds the dust shield on - 07119904511 - x 4
Hex Bolt - Holds the dust shield on - 2nd bolt - 34211164044 - x 4
Front: Stainless Steel Brake Lines - StopTech - 950.34531
Rear: Stainless Steel Brake Lines - StopTech - 950.34531
Brake Dust Shield Bolt - 34116868785 - x 4



Am I missing any other bolts or parts that I should be replacing? Can I use S2NHA part #s for most bolts and parts?

That little steel rotor set screw tends to corrode and lock the rotor onto the hub. I’ve seen it happen in as little as 10k miles. Some NeverSeize on the new threads can prevent that. Instead I use stainless steel rotor screws that resist corrosion- sold by Turner/ECS. See photos.

If your rotor screws are corroded on, don’t be overzealous since you’ll just destroy the phillips head. Here’s the method that I’ve been using since I was 19 that’s never failed me.

1) Spray rotor screw with PB Blaster, LiquidWrench or similar. (Make sure to rinse off the area at the end of the process with brake cleaner to remove residue.)

2) Vibrate the area around the screw to try to break the corrosion bonds between screw threads and hub threads. Tap/hit all around the screw with a plastic mallet, or use a steel hammer on a block of wood. This is similar to a lid on a jar that won’t turn off. Tapping the side of the metal lid all around on the kitchen countertop vibrates loose whatever is locking the threads.

3) Use a hand held impact tool with a hand held sledge hammer to remove the screw. (Inexpensive at Harbor Freight. See photos.) When the tool is hit with the sledge it first drives into the screw and then turns slightly. If done properly after several good hits the screw will turn. I’ve even gotten this method to work on a screw head that was completely destroyed by an impact gun.

First make sure to set the impact driver’s action to turn Off counterclockwise. It works like a ratchet and you don’t want it to be tightening instead of loosening. The tool comes with various bits. Install the phillips head bit that matches the screw head. Hold it solidly against the corroded screw and give it a single big wack with the mini sledgehammer. Then turn the tool back to its original position and give it another single wack. Continue. Be patient. It works.

Hope this helps!

[vel80]

Hi, I am considering doing rotors and pads on my F32 with base brakes (312x24mm front and 300x20mm rear). I bought 340 /345 calipers.

My VIN ends AG51226. ( 420i 2018 model )

I have problem what i need more to make this upgrade happen.

Please help.

[Tim.Rader]

Hello,

It's time for new brakes and I would, also, like to upgrade my 2019 F32 440 brakes. I am looking to just upgrade rotors and pads.

Vin ends in AG52646. Can someone plug into realoem and let me know what I have and what I can upgrade to?

Thanks,
Tim

[casualDIYer]

If trying to do this on a budget, having done it myself, these would be my preferences.

I like the Akebonos for pads. Stopping is as good as any other brand I've used including BMW and Hawk (both good), but the Akebonos include a brake sensor, which I really appreciate as a customer. From BMW the sensor is something crazy like $30 each. So save the $60 and get a set of pads with them included.

On rotors, I hate rusty hats so I splurged a bit (at twice the price of one-piece) went two-piece in the front and now counting the seconds to replace the rears. Two-piece rotors with aluminium hats do oxidize but they tend to turn grey, not awful rust. Some polish and an electric polisher clean them up well. Another satisfied Zimmerman customer here. Used them for years and happy with them. I've tracked them as well and both me and car remain in one piece so I guess they do the job I need.

As for blank vs slotted vs drilled vs slotted + drilled, some do look cooler than others but on a street car, is there an objective difference? I'm not crashing into things using blanks.

johnung notes the G2 caliper paint is good and I would also agree. You can use cheaper paint but it often doesn't resist heat or brake dust as well. The G2 kit comes with a reactor you add that hardens the paint that not only stands up to high heat but is effective at resisting brake dust staining, even using track pads. It only has one downside. The paint job has to be done all in one go.

Stainless steel brake lines? For me, I'd dump the money somewhere else, like a caliper rebuild for a used caliper. BMW's standard lines are fine. I'd replace them with new lines if you had a concern. I have a friend with a $300,000 Porsche GT3 RS and it uses rubber brake hoses. The majority of the braking system from pump to just before the caliper is already made of steel. The line in question is the last 6 - 12 inches. We land 200,000 lbs airplanes on rubber tires and all is fine. Rubber is a super material. I will say stainless steel lines do take out a little of the squish from the brake petal, altering brake feel. But some people really hate that and I have a feeling that is the reason car makers still use rubber.

Good luck on your project.

[johnung]

Originally Posted by Tim.Rader

Hello,

It's time for new brakes and I would, also, like to upgrade my 2019 F32 440 brakes. I am looking to just upgrade rotors and pads.

Vin ends in AG52646. Can someone plug into realoem and let me know what I have and what I can upgrade to?

Thanks,
Tim

The F3x 6-cylinder models only came with two brake options:

BLUE CALIPERS- M Sport factory option
Front 370mm x 30mm
Rear 345x24

GREY CALIPERS- Standard brakes
F340x30
R330x20

IMO Hawk 5.0 are the best street pads. See photo for part numbers. TireRack usually has best prices by a lot. But their website sucks so if it appears that they don’t carry them then just pick up the telephone or webchat with them live and give them the part number. They absolutely have them, often at $100/set less than others.

Last time I checked FCP Euro had OEM brake pad sensors cheap, like $18. Only need one front and one rear.

It’s only about $120 for a set of stainless steel brake lines. Well worth it to get rid of mushy brake pedal. See photo for StopTech SS part numbers. Turner has a nice set for a little more.

Plain Zimmerman rotors are great German made replacements.

Avoid dimpled or slotted rotors. No better performance and they are noisy. They are a BMW Marketing Department gimmick.

If you actually want a brake rotor upgrade with better performance, get full crossdrilled. They have best bite and are best in rain. That’s why BMW uses full crossdrilled on M3/M4. See photos for StopTech full crossdrilled part numbers.

Hope this helps!

[PininMargherita]

Originally Posted by johnung

The F3x 6-cylinder models only came with two brake options:

BLUE CALIPERS- M Sport factory option
Front 370mm x 30mm
Rear 345x24

GREY CALIPERS- Standard brakes
F340x30
R330x20

IMO Hawk 5.0 are the best street pads. See photo for part numbers. TireRack usually has best prices by a lot. But their website sucks so if it appears that they don’t carry them then just pick up the telephone or webchat with them live and give them the part number. They absolutely have them, often at $100/set less than others.

Last time I checked FCP Euro had OEM brake pad sensors cheap, like $18. Only need one front and one rear.

It’s only about $120 for a set of stainless steel brake lines. Well worth it to get rid of mushy brake pedal. See photo for StopTech SS part numbers. Turner has a nice set for a little more.

Plain Zimmerman rotors are great German made replacements.

Avoid dimpled or slotted rotors. No better performance and they are noisy. They are a BMW Marketing Department gimmick.

If you actually want a brake rotor upgrade with better performance, get full crossdrilled. They have best bite and are best in rain. That’s why BMW uses full crossdrilled on M3/M4. See photos for StopTech full crossdrilled part numbers.

Hope this helps!

Does it matter if the plain zimmerman rotors are one piece and not two?

[johnung]

Originally Posted by PininMargherita

Does it matter if the plain zimmerman rotors are one piece and not two?

For a replacement rotor on a daily driver, it doesn’t matter. If you were trying to shave weight and rotational mass on a track car, then that would be different. And we wouldn’t even be talking 2-piece rotors, we be using full floating 2-piece rotors that are many more times the cost.

[casualDIYer]

I sense a financial accident imminent. From Paragon



I hear these are pretty good. Mind you if I spent that much on rotors . . . . well . . . they'd be awesome.

Wait . . . is that Christmas music I hear?

[casualDIYer]

Originally Posted by PininMargherita

Does it matter if the plain zimmerman rotors are one piece and not two?

Zimmerman has, in terms of blanks, a one-piece rotor and a 2-piece rotor. This also applies to dimpled and slotted rotors. Zimmerman says they make a perforated rotor, which I assume is a 'drilled' and not 'dimpled'. Some part numbers to get you started.

340 x 30mm one-piece, blank, part number 150.2903.20
340 x 30mm one-piece, perforated, part number 150.2903.52
340 x 30mm one-piece, slotted, part number 150.2903.54
340 x 30mm one-piece, slotted AND dimpled, part number 150.2906.20

340 x 30mm two-piece, blank, part number 150.2903.32
340 x 30mm two-piece, slotted and dimpled, part number 150.2906.32

There are a few more details like Z coat, F something, black something, etc. Zimmerman dives into these details at https://www.otto-zimmermann.de

Good luck

[PininMargherita]

Originally Posted by casualDIYer

Zimmerman has, in terms of blanks, a one-piece rotor and a 2-piece rotor. This also applies to dimpled and slotted rotors. Zimmerman says they make a perforated rotor, which I assume is a 'drilled' and not 'dimpled'. Some part numbers to get you started.

340 x 30mm one-piece, blank, part number 150.2903.20
340 x 30mm one-piece, perforated, part number 150.2903.52
340 x 30mm one-piece, slotted, part number 150.2903.54
340 x 30mm one-piece, slotted AND dimpled, part number 150.2906.20

340 x 30mm two-piece, blank, part number 150.2903.32
340 x 30mm two-piece, slotted and dimpled, part number 150.2906.32

There are a few more details like Z coat, F something, black something, etc. Zimmerman dives into these details at https://www.otto-zimmermann.de

Good luck

Interesting thanks.

I’m working with slightly larger rotors:
Front Brake Rotors - Pair (370x30)

34106797606KTKT

I was hoping to find this in two piece smooth rotor but wasn’t successful so I landed on these

[PininMargherita]

Originally Posted by johnung

For a replacement rotor on a daily driver, it doesn’t matter. If you were trying to shave weight and rotational mass on a track car, then that would be different. And we wouldn’t even be talking 2-piece rotors, we be using full floating 2-piece rotors that are many more times the cost.

Makes sense. Yeah this is a road tripping touring build.