dgm8138

After I replaced mine over last winter, they burned up after the first session of the first day I was back on track. I could've had a lot more fun blowing $100 than by burning up some seals.

Does anyone just leave these off their track car?

User 52121

Interesting.

The boots on mine are pretty well vaporized too. Didn't think new ones would burn up that quickly though?

@futurz - you said "Brembo seals and boots" - are you referencing the silicone boots that RB sells? Or just that you bought the seals elsewhere and made sure to buy Brembo branded?

futurz

I bought the SS pistons from RB and the seals/boots elsewhere. I paid premium to get Brembo stuff. Might be worth it for the seals, but that will be the last time I will buy dust boots, no matter who its' from.

Shandingo

Do you mean that the sides of the pistons were pitted? How old were the pistons? What type of coating is on the pistons that was peeling?

Nickshu

Were you using the silicone "blue" high heat seals that RB sells? I know the stock ones burn up quickly, I wonder how the high heat ones hold up.

I just stumbled on this thread too...and earlier this week I just ordered everything (including SS pistons) from RB to rebuild my 996 C2 calipers this winter.

OP--FWIW if you call RB and order the full kit (seals, boots, pistons) they will give you bundled pricing that is not on their website. Saved me around $100 on the total.

serickson

The pitting that I have seen on my OEM pistons seemed to be caused by bad dust seal that allowed water to come in contact with the area of the piston that was exposed. Never saw pitting where the piston is inside the caliper. I replaced OEM dust seals with Stoptech gray silicone and they have lasted for years of DE and racing. This would be my recommendation for dust seals.

User 52121

Hey Steve! I think I saw your car @ Mark's the other day

-- Ptak

winders

It's my understanding the titanium is the better piston material.....

Nickshu

I've never seen titanium pistons at least for my 996 brakes. Titanium backing plates for the pad are out there. Certainly the stainless pistons from RB are better than the aluminum ones. Also they have "finger-like" contact points on the pad backings rather than a solid ring which likely transfers less heat as well. I've boiled my fronts on my 996 twice on the track...once on Superdot 4 fluid, once on ATE fluid. Now using SRF, expensive but worth every penny.

futurz

The coating on the OEM pistons literally flakes off. You can see the debris that collects in the caliper.
I don't know what the coating is made of.

d15b7

i never replace the dust boots on my race cars when i rebuild the calipers; they burn right up after a day on track. also, the piston to caliper bore clearance is definitely the loosest when everything is cold; typically i'll see some weepage after being parked for a week on the wheel and thats when i know that the seals definitely need to be replaced. if i take the car out on track with the weepy seals they stop weeping as soon as the brakes get hot and are ok for the rest of the day (one time arrived at the track for a race and at that point saw the weepage and raced it anyway, so that's how i know). typically i can spot the weepage before a race weekend during the nut and bolt and go ahead and rebuild BEFORE the race! so, seal to piston clearance is definitely the biggest when cold and closes up when hot

RacingBrake

Dust boot serves the purpose to prevent dust/water from going inside pistons thus can prolong the life of caliper seal and pistons (=caliper life)

RB blue boots are specially made of Silicon material (vs. standard boots of EPDM) for track applications, it can resist temperature up to 450 deg F (vs. EPDM 300 F), which is usually above most track applications so they will never got burnt our like standard boots. (Reminder: Must avoid contacting brake fluid during installation)

RB stainless steel pistons are machined from stainless steel bar stocks for high strength and rigidity under the heat. Its bores are featured with thin wall cut to reduce the weight gain over aluminum pistons.
The outer surface receives a very fine grinding before chrome plating and final lapping finish to maintain an ultra smooth mirror like surface with a tolerance of .0015", and a very hard surface that is highly resistant to corrosion and abrasion. Also added to the brake pad backing plate contact circular surface is the vent cut, which not only can reduce the heat transfer to the caliper but also help in brake release.

None of these feature can a conventional OE aluminum piston, nor expensive Titanium piston offer.

A lot of "details" is working into our caliper rebuild components to ensure your Porsche calipers can be rebuilt with only 3 simple components; Piston, Seal, Boot, no matter how OE calipers constructions are. And after rebuild you'll know why your OE calipers can not only perform better, but also last a lot longer.

We are shipping OE caliper rebuilt kits daily (most are track customers) for many years and yet to see any customer that needs to "rebuild" their calipers after rebuilding with RB components.

http://www.racingbrake.com/category-s/7185.htm

RacingBrake

Illustration to RB SS Pistons:

Nickshu

^^^ I just got my SS pistons from RacingBrake. They are very nice looking and appear well finished. Measuring w/ my dial caliper shows very consistent surface.

PorscheDoc

I run 6 piston front gt3 and 4 piston rear gt3 on my 951 with racing brake's SS pots for the last couple years and they have worked out fantastic.