Porsche 996 Brembo BBK Conversion Install

[duracellttu]

So just to be clear, there is no way to press the pins back because of the dowels. The only way to get the pins centered are to offset with washers or use a dremel to shave them down?

[Tbonem3]

Roll pins. Dowels go in between two mating faces.

This was an issue for a few people on m3forum. I would grind/file the pins down a hair.

[maupineda]

I took some measurements and I think the pins in the callipers are not really an issue. Please see the image below with some references I added.

A --> B = 61MM
A --> C = D --> B = 19mm
A --> E = F --> B = 19mm
C --> D = 23mm

Based on the above, the pins are centred in the rotor ditch of the calliper.




I still have tape on the pins as I have my clear coat pending, but I am for sure not 3mm off as I saw when mounted for fit test. at least not in my case. the pins' length is symmetric side to side so if I center my rotor between them, I am centring the rotor in relation to the calliper monoblock.

I hope this makes sense and is useful to others.

[HighOnLSB]

So I am following this DIY to install my 996 brakes finally over the last couple days and have run into this issue regarding pin clearance on one of my rear calipers as well.

I purchase a mismatched set of rears, but with correct part numbers for our application, and seem to have one carrera and one boxster caliper. The carrera caliper has perfect pin clearance on both sides of the rotor, however the boxster caliper does not.

When I originally mounted the caliper with p0lar brackets it was a tight fit but I thought it was nothing serious. Turns out the outboard pins were binding on the rotor and I never noticed. After a quick test drive I find out that the outer face of the rotor has been damaged. A new rotor and new RallyRoad brackets later and I am trying to tackle this issue properly this time now that I am aware of what’s going on.

Does anyone know what the minimum clearance needs to be? Even with the supplied washers from RallyRoad the outboard pins are very close to the surface of the new rotor, maybe only 1-2mm clearance. Is this enough clearance to be safe? Or do I need to continue to try to remove material from the pin?

[duracellttu]

I took some measurements and I think the pins in the callipers are not really an issue. Please see the image below with some references I added.

A --> B = 61MM
A --> C = D --> B = 19mm
A --> E = F --> B = 19mm
C --> D = 23mm

Based on the above, the pins are centred in the rotor ditch of the calliper.




I still have tape on the pins as I have my clear coat pending, but I am for sure not 3mm off as I saw when mounted for fit test. at least not in my case. the pins' length is symmetric side to side so if I center my rotor between them, I am centring the rotor in relation to the calliper monoblock.

I hope this makes sense and is useful to others.

so are you saying this is a RR adapter tolerance issue?

[maupineda]

So I am following this DIY to install my 996 brakes finally over the last couple days and have run into this issue regarding pin clearance on one of my rear calipers as well.

I purchase a mismatched set of rears, but with correct part numbers for our application, and seem to have one carrera and one boxster caliper. The carrera caliper has perfect pin clearance on both sides of the rotor, however the boxster caliper does not.

When I originally mounted the caliper with p0lar brackets it was a tight fit but I thought it was nothing serious. Turns out the outboard pins were binding on the rotor and I never noticed. After a quick test drive I find out that the outer face of the rotor has been damaged. A new rotor and new RallyRoad brackets later and I am trying to tackle this issue properly this time now that I am aware of what’s going on.

Does anyone know what the minimum clearance needs to be? Even with the supplied washers from RallyRoad the outboard pins are very close to the surface of the new rotor, maybe only 1-2mm clearance. Is this enough clearance to be safe? Or do I need to continue to try to remove material from the pin?

I think you will be fine. the rotor is 20mm thick, and the spacing between the pins is 23 (at least in my set, which is also from a Boxter S), so there is will only be 1.5mm on each side. with heat, the disc will expand radially only so you will be ok.

[duracellttu]

For those who are using the Rally Road rear adapters, the the kit came with a set of socket cap hex bolts with locking washers. Did any of you try to source flat washers so the locking washer didnt tear up the powder coat / paint? The calipers has an odd sized shape that would require a 20mm outer diameter and M12 (12mm) inner diameter washer. Not having much luck finding one off the shelf at the local hardware store.

What are you guys doing?

[Tbonem3]

You don't want tension?

[Titaniu//M]

For those who are using the Rally Road rear adapters, the the kit came with a set of socket cap hex bolts with locking washers. Did any of you try to source flat washers so the locking washer didnt tear up the powder coat / paint? The calipers has an odd sized shape that would require a 20mm outer diameter and M12 (12mm) inner diameter washer. Not having much luck finding one off the shelf at the local hardware store.

What are you guys doing?

When I painted my calipers, I masked off the entire contact surface that the washer sits on. I think it's best to leave that part unpainted- then there's no way to tear up the paint/powder coating. Paint can expand/contract as it heats up or cools down and affect the tension of the bolt.

[Johnvu]

When I painted my calipers, I masked off the entire contact surface that the washer sits on. I think it's best to leave that part unpainted- then there's no way to tear up the paint/powder coating. Paint can expand/contract as it heats up or cools down and affect the tension of the bolt.

100% agree here. If you have powder coating on the caliper where the contact points are, you need to sand it off until you get down to a smooth metal surface. The last thing you want is for the bolt to come loose at a track day or from continuous heavy braking.

It looks pretty fully powder coated but it can result in a crash or your caliper falling off... LOL.

[duracellttu]

Thanks for the responses. I’m going to sand them down

[r4dr]

I'd consider red Loctite or equivalent on the bolts holding the adapter to the hub as well. It will be a bitch to get it off if you ever need to, but huge fan of that over a bolt backing out.

[Titaniu//M]

I'd consider red Loctite or equivalent on the bolts holding the adapter to the hub as well. It will be a bitch to get it off if you ever need to, but huge fan of that over a bolt backing out.

If you run dampers, you will need to pull the caliper off to swap pads. You'd be shooting yourself in the foot putting red loctite on the bolts. Maybe blue (non-permanent) loctite will do if you are paranoid.

[r4dr]

Don’t the calipers mount radially to the adapter bracket? The bracket doesn’t have to come off for servicing dampers does it?

[WOLFN8TR]

Don’t the calipers mount radially to the adapter bracket? The bracket doesn’t have to come off for servicing dampers does it?

The dampers have 3M adhesive on them which sticks to the brake pads so you can't just pull them out.