Bertrand Daoust

Hi Guys,

I notice that few of my caliper's dust boots are cut. So I think that I will have to change them.
As I have never done that, my question is:
Do I have to take the piston completly out (one by one) or I can leave them in place to change the dust boot?
For now, I'm not planning to change anything else (seals and pistons).

Thank you.

Leon Speed

I think it should be possible to leave them in. If you're looking to leave the calipers on the car, then it might be very difficult to remove the old ones. Good access is required. So, maybe possible. Worst case, they need to come off. Btw if the pistoms come out, it makes sense to change the inner seal as well.

Bertrand Daoust

Thanks Aryan.
The 4 calipers are out of the car so quite easy to do anything.
Good point on the seals.

Bilal928S4

I think you can only get the rebuild kit with piston, seals and dust boot. I don't think the dust boots are available seperately.

Rob Edwards

Nah, you can get the dust boots alone. Zeckhausen is cheapest.



http://www.zeckhausen.com/Brembo/Con...es.htm#Rebuild


http://www.allzim.com/acatalog/Bremb...ust_Boots.html

http://www.paragon-products.com/Brem...-kits-late.htm

EDIT: I know you know this, but you really want to clean the living crap out of the caliper surfaces around the dust boots before you yank the old ones. The last thing you want is any dirt or grit getting between the piston and caliper bore.

namasgt

That first link posted only sells stop tech stuff, they dont fit properly and the quality of the dust boots are very low compared to the Brembo ones. Their dust boot does not fit right and so thin that you could easily damage them during the install. I bought mine from paragon and they only sell Brembo.

Rob Edwards

Ali-

That's good to know- I have only bought complete caliper rebuild kits from Porsche, and in truth none of the calipers really needed to be rebuilt- the inner seals were fine, bores and piston surfaces were perfect, etc. If Bertrand has torn boots, he should be fine with those alone.

Bertrand Daoust

Thank guys.
I removed all the dust boots this morning.
I decided to remove the pistons with compress air. Did it with about only 40 t0 50 lb whitout any problem.
The only small problem was with few dust boost that were quite hard to remove from the caliper, even with the piston out. Use a very small screwdriver to pry it out.

Thank you Rob for your excellent right up:
http://forums.rennlist.com/rennforum...not-to-do.html

Ali: I was thinking going with the Brembo too. Read some not very good things on the Stopteck ones.
I don't know if Roger keeps the Brembo dust boots and seals?
As my piston are still in very good shape, I don't want to spend big money on full kits.

Leon Speed

I ordered seals, boots and pistons from Porsche for all four calipers (yike$) and IIRC all three were available separately per caliper. So you can probably get just dust boots, but in quantity of four.

Pistons can be a pain to get in because of the low tolerance between cylinder and piston. I remember one piston getting wedged and a few were hard to push in past the new seals in the middle of the cylinder.

Oh yeah since you took the pistons out, you probably will need piston lube. Can get it from Porsche, but that would be way to much for what you need. Unfortunately only new pistons come with piston lube in the package.

ROG100

Porsche only sells the kit - piston, seals.

Paragon is your best bet as they have the Brembo parts and Ali checked it out.

namasgt

There is also two types of Brembo dust boots. They both have the same part number and lettering. The only way you can tell the difference is that on one all the numbers and letters are large and on the other one their small. I have got both types from Paragon. You can easily feel that the one with the larger letters has more meat and feels tougher. My guess is that the one with larger letters is newer and what Brembo is making now and the one with smaller letters is just old stock. In either case, both are alot better than Stop Tech.

Bilal928S4

Can somebody provide the sizes required for the front & rear calipers (and quantity of each size) required for the various years.
I am interested in 90 S4 and 91 GT.
thanks

Bertrand Daoust

On mine, I have the two kinds on the front ones. 3 with larger letters and 5 others with the small letters. I'm quite sure they're original. Weird!
Anyway, time to order new Brembo dust boots.

Thanks again.

Bertrand Daoust

Just mesured mine - 91 S4 - to order the right ones as the part# on the boot itself does'nt match the ones Paragon have.
They're in front: 4 x 44mm and 4 x 36mm.
In the back: 4 x 30mm and 4 x 28mm.
This is all pistons diameter.

Quite sure they're the same for your S4. Not sure for the GT though.
Porsche change sizes in 89. See Bill's thread (#5) here.

https://rennlist.com/forums/928-foru...ifference.html

coloradocayenne4

where do I get just the seals for a set of 997 6 piston calipers up front in the UsA, i want oem brembo.