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Macan Brembo owners who track their Golf, pls weigh in.

Bernb6

Go Kart Champion
Location
Palo Alto, CA
Car(s)
2017 GTI Autobahn
BBK's generally have a number of potential advantages over GTI's PP brakes - IF you're currently taking your brakes to their heat limits.

1. Much better heat dissipation leading to
2. Much longer rotor life
3. Better pad life
4. Longer fluid life
5. Better brake feel
6. Easier pad changes*
7. Unsprung weight
8. Front to rear pad taper

Before I get flamed, let me say that I'm not advising people to go BBK. It's not needed in most cases. But the question has been asked about the (potential) benefits and these are the ones I have experience with. And I'm talking about my experience with Stoptech - other systems may be comparable or better in some aspects. I'm also not talking about value - how anyone spends their money is up to them.

Improved heat dissipation is a function of larger surface area and improved air flow through the center of the rotors. Internal vanes are curved to provide more centrifugal effect pulling air through the rotor and the open center allows more air in. If your calipers are discoloring or you see small cracks in your rotors, then they are getting pretty hot.

Two piece rotor material is different from single piece rotors and provide more thermal stability and much longer life. In extreme heat, single piece rotors are constrained in their thermal expansion and warp in the shape of a sombrero. Floating rotors simply expand as a flat ring. It's unlikely that many of us would be getting our stock rotors up to these temps but if you see your pads tapered such the the outer edges are thicker or thinner than the inner, this is the cause. Overheating rotors may need to be replaced because of large thermal cracks rather than wearing too thin. And the metal composition leads to much longer wear - in my personal experience, up to 4-6 times longer.

Pad life is affected by two factors: temperature and proper bedding. Overheated pads crumble, crack or glaze. Properly bedded brakes result in a thin layer of pad being laid on top of the rotor - you can see the color change when this is done and as it wears off. Proper bedding reduced the possibility of glazing and reduces both pad and rotor wear. Of course, street pads won't survive heat as well as track pads. If the rotors are 200 degrees cooler, pads last longer.

You've probably all seen night time photos of rotors glowing on race cars. Glowing happens at 900 degrees and higher. We are unlikely to be doing that but certainly can get to 600 and higher depending on our equipment and how we drive. A friend and I compared caliper temps coming into the paddock at Sonoma. My BBK temps were more than 100 degrees lower than his Macan calipers with PP rotors. But for most of us, using quality 600 or 660 fluid is enough to prevent fluid boiling.

*Stoptech calipers are not mono block. Once the wheels are off, pad changes take only a few minutes because the pads are quickly accessible from the top of the calipers. This also makes it easy to flip the pads to even out wear between inside and outside.

Stoptech BBK reduces weight at each wheel by 12 pounds over PP brakes Comparative weights (note, prices have gone up substantially since the price noted in the link)

Most multi piston calipers have a smaller piston at the caliper's leading edge since the the leading edge of the pad gets hotter. Macan calipers share this feature. But the GTI location of the caliper is reversed, so that the larger Macan piston is at the leading edge. In extreme use, this will exacerbate pad taper.

Bern
 

turbojzrr

Go Kart Champion
Location
San Francisco Bay Area
Car(s)
'19 Golf R
Two piece rotor material is different from single piece rotors and provide more thermal stability and much longer life. In extreme heat, single piece rotors are constrained in their thermal expansion and warp in the shape of a sombrero. Floating rotors simply expand as a flat ring. It's unlikely that many of us would be getting our stock rotors up to these temps but if you see your pads tapered such the the outer edges are thicker or thinner than the inner, this is the cause. Overheating rotors may need to be replaced because of large thermal cracks rather than wearing too thin. And the metal composition leads to much longer wear - in my personal experience, up to 4-6 times longer.
I think this is definitely true, and I was wondering how much the caliper itself adds compared to the rotor for heat dissipation.

The two-piece rotors can be added to Macan's too right?
 

burgerkong

Drag Racing Champion
Location
Ontario, Canadeh
I think this is definitely true, and I was wondering how much the caliper itself adds compared to the rotor for heat dissipation.

The two-piece rotors can be added to Macan's too right?

The key is in directionally vaned rotors, doesn't matter what calipers you run.

I do not think it's fair comparing a caliper upgrade to a full blown BBK. The Macan sits in a little niche spot, much like the TTS. Fairly priced, and for most people the looks is enough. Pad taper happens regardless of differentially bored pistons or not, it's a fact of racing/tracking.
 

bobivy1234

Go Kart Champion
Location
Greensboro, NC USA
Car(s)
2016 VW Golf GTI
I think this is definitely true, and I was wondering how much the caliper itself adds compared to the rotor for heat dissipation.

The two-piece rotors can be added to Macan's too right?
Sure, just grab any 345x30 2-piece rotor assuming the hat offset matches the R32/MkVI R hub. Stoptech/ECS/Neuspeed and others sell these and even mention the Brembo upgrade for its use. Some are semi-floating (radial expansion only) and others are full-float (radial+axial). The Macans don't not have an ideal piston setup compared to BBKs that have vented/titanium/staggered pistons but with some titanium shims and veined 2-piece rotors, I can't see at the end of the day how the Stoptech ST-40 would completely out-cool the Macans (I've got to see it for myself I guess). The only ST-40 that really makes sense is the 356x32, the smaller one 328x28 should be a wash compared to the Macans with 345x30. The BBKs also have more rigidity (center bracing, forged materials, etc) compared to Macans which probably helps at high speed braking for compliance. Quick area math of different rotor sizes:

328x28 -> 2364696 mm^3
345x30 -> 2803038 mm^3 : +16% area
356x32 -> 3183608 mm^3 : +12% area

Talking pad size, the Macans run a 132x77 backing plate with 62mm depth pad and the ST-40 is a 132x71 plate with 51mm depth pad so the sizes are about identical favoring the Macans. My test in '22 is to run the Macans with budget 2-piece directional rotors (ECS semi-float), good fluid, front/rear race pads (ST-43:F, XP8:R), Ti front shims and I'd be surprised if they can't keep up. If they can't, then I've got to really re-evaluate my braking situation.
 
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Bernb6

Go Kart Champion
Location
Palo Alto, CA
Car(s)
2017 GTI Autobahn
I agree that vast majority of the heat dissipation benefit is due to the two piece rotors. Neuspeed has a set for under $800 Neuspeed that might be a good match with the Macans. ECB also has a set.
Bern
 

bobivy1234

Go Kart Champion
Location
Greensboro, NC USA
Car(s)
2016 VW Golf GTI
Would the 340mm floating 2 piece from the girodisc work with the Macans?
Technically you should be using 345x30, that is the best fitment since that is the Mk6/R32 spec rotor and not 340x30 like the Mk7 that has been tested to fit the Macan brakes the best. I and others run 345x30 blank Zimmermans and I'd match the 2-piece to be 345mm as well. You can get away with 340 but your pad swept area might not be perfect.
 

Bernb6

Go Kart Champion
Location
Palo Alto, CA
Car(s)
2017 GTI Autobahn
Would the 340mm floating 2 piece from the girodisc work with the Macans?
I've always thought the Girodiscs were the gold standard for two piece rotors. If the size is right, they should be great.
Bern
p.s. I had a pair of Girodiscs (another car) about 5 years ago and they cracked the first day on track! Girodisc was apologetic, explained that they'd had a bad shipment of raw material, and replaced the rotors within days.
 

Bryans12v

Ready to race!
Location
Hudson Valley, NY
Car(s)
19 GTI, 22 Tig Rline
Would the 340mm floating 2 piece from the girodisc work with the Macans?


Works just fine with the standard A1-171 340mm disc's from Girodisc.
 

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GTIfan99

Autocross Champion
Location
FL
Works just fine with the standard A1-171 340mm disc's from Girodisc.

For the 100th time, that isn't necessarily true. It all depends on the pads you use if you'll have issues.

Please don't make definitive statements about fitment, that's how people end up with issues and get upset.
 

Bryans12v

Ready to race!
Location
Hudson Valley, NY
Car(s)
19 GTI, 22 Tig Rline
For the 100th time, that isn't necessarily true. It all depends on the pads you use if you'll have issues.

Please don't make definitive statements about fitment, that's how people end up with issues and get upset.

100th time? I see no other mention of this here.

So the proper pad set for macan calipers are sold in different sizes for this caliper with the same backing plate?

I made a statement that its works on my car with the pads I used, so yes it is possible. I didn't say it would work with EVERY pad option. Noone can make that claim unless they try every pad option available.
 

GTIfan99

Autocross Champion
Location
FL
100th time? I see no other mention of this here.

So the proper pad set for macan calipers are sold in different sizes for this caliper with the same backing plate?

I made a statement that its works on my car with the pads I used, so yes it is possible. I didn't say it would work with EVERY pad option. Noone can make that claim unless they try every pad option available.

It's been repeatedly covered in the Macan thread. Literally in the first post. The pad is what determines if 340mm will or won't work.
 

scrllock

Autocross Champion
Location
MI
Most multi piston calipers have a smaller piston at the caliper's leading edge since the the leading edge of the pad gets hotter. Macan calipers share this feature. But the GTI location of the caliper is reversed, so that the larger Macan piston is at the leading edge. In extreme use, this will exacerbate pad taper.

Bern
I was under the impression that the macan pistons are 42mm all around. Are you thinking of the TTRS caliper (40/44?)
 
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