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

[Pklauser]

Sidenote for all, FCP now carries Girodisc rotors.

👀👀👀

Here's the link to the E46 ones: https://www.fcpeuro.com/products/bmw...irodisc-a1-012

Slightly awkward that you'd be exchanging the whole disc when you could theoretically just swap the rings.

[SQ13]

Good point on the rotor width - would be nice if it was possible to run 345x32 rotors with the Porsche calipers. I’ve been thinking about making the switch to Girodisc. I’m not tracking the car enough these days to justify buying from FCP at MAP and using their exchange program, so I’ll prob just wait for the next Girodisc sale and buy elsewhere.

TBH if lots of GT3 owners are tracking their cars with cracked boots, I’ll likely do the same until a definitive solution is found. Replacing the boots after every DE doesn’t sound fun lol.

[mrgizmo04]

would be nice if it was possible to run 345x32 rotors with the Porsche calipers.

I don't think it is. Pcar fronts are made for x28 stock Pcar discs (rears are made for x24, while we run them on x20, so don't let rear pads get too low ). While you can shave those pins/pad stoppers to fit a wider disc, you'd prob get rubbing as the middle part of the caliper is not wide enough. You are talking about tacking on 2mm on each end. I got so much radial expansion from the rotors that I got rubbing of the outer edge of the rotor on the caliper edges. Then also, to fit a wider rotor, since you are not widening the caliper, you'd need to shave 2mm off each pad (more if you want to run ti or other shims). Then you are losing heat capacity out of the box on the pad. I posted somewhere the size of the front Pcar pad is barely larger than stock M3 pad, so pads don't need any help getting overheated to start with.


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[OPS]

TBH if lots of GT3 owners are tracking their cars with cracked boots, I’ll likely do the same until a definitive solution is found. Replacing the boots after every DE doesn’t sound fun lol.

I wouldn't run any dust boots if I was tracking that much tbh - its a waste of money and since your inspecting/cleaning the brakes after each event, no reason to!

I ran the dust boots on my E46 with 18z and 996 C4S and E90 M3 Rotors with no issues however I was on Michelins so heat wasn't as much an issue.

What I really wanted was an AP BBK....

Mike

[D-O]

First ever track day. It seems I was not terribly hard on the brakes as my plain-Jane Centric dust boots held up.




This is the fist time I have noticed that the pads are a bit too tall and extend just a bit above the top edge of the rotors. They do fit nicely at the bottom. Is this to be expected?

[OPS]

Centric made the parts for stoptech and in 95% of the applications I recommended them. You have tons of pad which in itself is a nice thermal barrier. I would take out the pads, clean them up, and put them back in. But overall I wouldn't loose any sleep over that!

Mike

[mrgizmo04]

First ever track day. It seems I was not terribly hard on the brakes as my plain-Jane Centric dust boots held up.




This is the fist time I have noticed that the pads are a bit too tall and extend just a bit above the top edge of the rotors. They do fit nicely at the bottom. Is this to be expected?

What street pads were you running?

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[mrgizmo04]

[QUOTE=D-O;n276867

This is the fist time I have noticed that the pads are a bit too tall and extend just a bit above the top edge of the rotors. They do fit nicely at the bottom. Is this to be expected?[/QUOTE]

Yes, once you get seriously moving and put enough heat in, the rings will expand radially and grind that off.

That said, at slower pace, you don't need to do anything with that edge, it will crumble away naturally, so you don't need to take anything out to clean.

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[D-O]

What street pads were you running?

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Hawk ceramic. I am not crazy about them. At the time the car was my daily, and I bought them in the hope that they would be clean. They have not let me down on that.

[heinzboehmer]

Just another data point. Girodisc dust boots did not survive either

Swapped to a brand new set of Girodisc dust boots and installed the Bry5on scoops. Boots still look fine after a track day!

Same pads, same fluid, same track, same basically everything. Only real difference was the addition of the scoops. More analysis here: https://nam3forum.com/forums/forum/m...142#post279142

[Tonggi]

glad I read this thread, before I invest more money into thi skit which ran perfectly fine at Sebring in HOT florida weatherr. I am scared to cehck the boots. I might just use this as an excuse to buy an AP KIT

[heinzboehmer]

glad I read this thread, before I invest more money into thi skit which ran perfectly fine at Sebring in HOT florida weatherr. I am scared to cehck the boots. I might just use this as an excuse to buy an AP KIT

Well, no dust boots on the AP calipers, so you definitely wouldn't need to worry about them then

[audipwr1]

Demon Speed sells uprated boots
On these calipers in hard use environment expect 25-50hrs out of the dust shields max, its the rebuild cycle on my racecar with effectively this brake
The ceramic pucks help but fall out all the time and are a pain

[OPS]

We are always here also should you need another choice for silicone boots and/or pistons. Frenkit performance just finished their trade show in Germany two weeks ago.

[heinzboehmer]

Yeah I don't expect these dust boots to last forever with the cooling scoops, but I'm happy knowing that they do extend the service life.

The OPS/Frenkit boots are next on my list to try. OPS do you sell just the dust boots? All I see on your website are kits comprised of boots + seals.