Porsche Brembo 996 BBK Conversion-- let's figure out how to fix the dust boots

[mrgizmo04]

So I installed the RacingBrake seals from above, and it looks like I'm going to have the same issue mrgizmo04had here: https://nam3forum.com/forums/forum/m...511#post229511

The dust boots for the smaller piston don't have enough friction to stay in place. I plan on reaching out to RB about this, these weren't cheap!

Don't remember if I posted this, but this is an issue with using Stoptech/Brembo/Girodisc dust boots on these 996 calipers. I don't know why, some bore spec is off somewhere. Several kits from Brembo and several kits from Girodisc, still same issue. Stoptech boots in Stoptech calipers no problem, Brembo boots in Brembo (GT kits not these 996) calipers no problem. The way I "solved" the issue is I squeeze deliberately yet gently on the outer metal ring of the dust boot to slightly deform it to make it oblong/oval (very slight). And it seems to stay in.

🤷♂️ I'll live with it with that slight workaround.

Happy motoring!

Sent from my SM-S911U1 using Tapatalk

[Pklauser]

So I installed the RacingBrake seals from above, and it looks like I'm going to have the same issue mrgizmo04had here: https://nam3forum.com/forums/forum/m...511#post229511

The dust boots for the smaller piston don't have enough friction to stay in place. I plan on reaching out to RB about this, these weren't cheap!

[Obioban]

Would you advise running these high temp seals in daily street use? I'm contemplating swapping out my CSL/CS spec'd brakes with Megane RS Trophy-R / Buildjounal fronts with 996 rears on my e46 "m3" touring. I think can will see 2 / 3 track days a year at most.

I plan to do it, but, since I have zero experience with it (yet), don’t think I should recommend it.

[puma1824]

Update: High temp silicon seals held up!
(https://racingbrake.com/bp-404bs/)

Car was doing double duty, running in instructor and advanced group, back to back, all day. He was not running backing plates.

Disclaimers; 50-60 deg ambient and summit point raceway (not that hard on pads), so not WORST case scenario-- but I'm stoked. Will be installing this winter.

Would you advise running these high temp seals in daily street use? I'm contemplating swapping out my CSL/CS spec'd brakes with Megane RS Trophy-R / Buildjounal fronts with 996 rears on my e46 "m3" touring. I think can will see 2 / 3 track days a year at most.

[Casa de Mesa]

Hell yeah. That's fantastic news.

[Obioban]

Update: High temp silicon seals held up!
(https://racingbrake.com/bp-404bs/)

Car was doing double duty, running in instructor and advanced group, back to back, all day. He was not running backing plates.

Disclaimers; 50-60 deg ambient and summit point raceway (not that hard on pads), so not WORST case scenario-- but I'm stoked. Will be installing this winter.

[heinzboehmer]

Awesome, thanks for the link

[Obioban]

Looking forward to that too. Do you know where those are from?

At least the boots are easy to swap without removing anything besides pads...

My friend got the "high temp" (I believe silicon?) seals from here: https://racingbrake.com/bp-404bs/

He has an event 10/17.

He's quite quick, so should be a good test of them.

[heinzboehmer]

Curious if the piston seals are affected by the high temp.

I was unable to find Brembo seals when I rebuilt my calipers, so I used the girodisc ones. Supposedly made for high temps and track use, but we'll see.

[Epsilon]

Curious if the piston seals are affected by the high temp.

[heinzboehmer]

Womp.

Looking forward to seeing how the high temp dust boots hold up on my friend’s car.

Really hoping they hold up, as I don’t want to be dealing with heat shields (or, worse, both combined aren’t enough).

Looking forward to that too. Do you know where those are from?

At least the boots are easy to swap without removing anything besides pads...

[Obioban]

Womp.

Looking forward to seeing how the high temp dust boots hold up on my friend’s car.

Really hoping they hold up, as I don’t want to be dealing with heat shields (or, worse, both combined aren’t enough).

[heinzboehmer]

Brembo dust boots did not survive a track day . Granted, this track day was extra long, so the brakes got a good workout. 7, 30 min sessions vs the regular 5, 20 min sessions.

Setup was 996 calipers, ZCP rotors, PFC08 pads, titanium shims and brake ducts (which are kinda useless with the new rotors). Even with the cooling/heat shielding, this still happened:



That was the only boot that fully failed, but I found a few others that were a bit melted. Replaced with a girodisc one for the time being. I'll likely replace all of them before the next track day just to see how those hold up.

[mrgizmo04]

That was day 2 of that pad being used...

... though admittedly in a caliper that got stuck.

One day too long . Past half point on the pads, this kit just doesn't have the capacity or evacuation efficiency. Once combined with rotor being less than half life, it gets more interesting yet, need to keep optimizing. FCP might drop our warranty sponsorship if we keep sending back half good pads/rotors.

Sent from my SM-S911U1 using Tapatalk

[mrgizmo04]

Just my gut feel says there is something to that. The thickness and mass of the new brake pads creates a thermal barrier for the caliper and boots. Do folks use titanium heat shields as well? Like these:

https://girodisc.com/titanium-shield...c2s-c4s-front/

Yes I run 1mm hardbrakes.com version, but girodisc makes their own version.

To reiterate, I run 1mm (believe thickest they make) Ti shims with Vorshlag cooling deflectors (which move more air than hoses) and still have issues with dust boots.

Sent from my SM-S911U1 using Tapatalk