koenig_roland

hi Guys,
as i have the 964RS brake on my blue car and that car is mostly used on trackdays.. i have the issue with cracks in my 322 brake discs.

The car weights round about 1230kg (without driver) has the air-shields behind the brake disc in the front removed (cutted to protect the ABS sensor) and i use Pagids at the track. Best combination for me is orange in the front and blues in the rear. Brake is the complete 964RS setup. The rear is fine. The crazy expensive rear-disc lasts quite long...

The front brake is at tracks like Redbull Ring (one of the hardest tracks in europe for clubracing in context of braking...) at the absolute limit. Even the fast guys with the GT4 and with the 96GT3 are on the limit with the brakes...

My brake is fabulous there, but after one trackday, i have some cracks in the discs and after another day (with that pre-cracked discs), the cracking increased and i have to exchange the discs. I have tried turbo 3.6 discs (cheaper, but nearly 1kg heavier) und now 964 RS discs.. both solutions do not last long....

What options do i have to achieve a more duralbe solution there?

One of my buddies has 996TT brakes at his 964C4 fitted and that seems to be better... but i would prefer to stay with the orig. 964RS solution and have a better disc...

One idea would be, to give coleman racing discs a try... But, a possible solution must make sense in economical reasons... girodisc (labeled colemans) is to expensive here in germany....

Do you have an other option for me?

964RS disc is round about 250 - 300,-€ per disc here in germany... That is ok, but it should last at least as long as one set of pads....

thx

best regards

thilo

PAOLOP

koenig_roland

HiWind

Roland i specifically run slotted instead of drilled rotors - AP, PFC, Giro, Coleman etc.. have options.

The slots work better for track cars per my experience with the ones I run on my Cup & 964 RS.

Bill Verburg is the brake guru so his posts usually help alot in 964 or 93 fora.

https://rennlist.com/forums/993-foru...eed-ideas.html

I went this route but have used Giro too

https://rennlist.com/forums/964-foru...l#post12534197

Bill Verburg

holey disk crack out much more quickly than solid or slotted

for 964 322x32 front disk w/ standard 964 wheel carriers you can substitute 928GTS 322x32 disks. The 928s are plain. They will still eventually crack out but it will take longer.

koenig_roland

and how is this australian company called? Is it DBA - which i already found?

Perhaps, i have to add one of those cooling-air hose solutions directly to the rotor...?!

koenig_roland

thx bill. But the 928 disc is sadly even more expensive here in germany...

Perhaps i change my configuration to 996TT calipers with 330mm discs.... The disc cost just a fraction of the 322mm discs and there is an adapter available, that makes the caliper fitting to the 964...

tdiquattro

yes big reds look great, as do holed discs. I know it doesnt help, but honestly 993 C2 all round does the job, never fade on track and are so cheap to keep running. I would guess the same or less unsprung.

I would sell the setup, make some money and convert to 993 fronts, solid discs all round. Discs are 35 euros each. For a track car surely running costs/off the shelf maintenance/easy parts supply is part of the design.

PAOLOP

I think Thilo look for two-piece discs to be mounted directly with front caliper RS ​​/ Turbo 3.3. What on the market?

koenig_roland

exactly... will ask coleman for a rough price-tag but have to meassure some old discs before and handover the spec-sheet...

Steve Weiner-Rennsport Systems

Hi,

JMHO, but quality-wise, Colemans are not as good as OEM Porsche, based on personal experience.

We use a slotted Alcon 332x32 rotor/hat assembly that is FAR better than any OEM rotor and outlasts them 4:1. Not cheap, but you get what you pay for.

The other thing I would do is change brake pads to shift some of the thermal loads to the rear. I like using Pagid RS-29 up front and RS-14 in the rear. Naturally, a good LSD is needed for this combination.

Hope this helps,

cobalt

I haven't had any issues with the coleman disks. I went from the 964 turbo 3.6 rotors to coleman slotted and I no longer have the cracking issues I used to. Dual driver car and it has never been an issue for me. The cast hole on the other hand crack very easily for track duty. Although added brake cooling seemed to help as well.

Why are rotors so expensive there? 928 rotors run $185 ea, 94 turbo 3.6 $196 ea and the 3.3T/RS $149.69 in the US and these are prices for factory parts.

If you don't want to use a custom hat use an adapter for the 993TT and just use 993 used hats with custom slotted rotors. This option definitely will crack over time but the cracks are ones I can live with.

I also use the pagid R-29 front R-14 rear setup with my 993 RS brake setup. I can get a few thousand miles of track days out of them before it is time to replace.

PAOLOP

The problem is in the hats: different disk offset Turbo 3.6 Vs Turbo 3.3/964RS.
Thilo, You need custom hats; who make these?

cobalt

The 3.6T and 3.3T/RS use the same offset the 993TT is 5mm shorter. The differences between the 3.6 and 3.3/RS discs are the less surface area or face of the disc for the 3.3/RS which uses the 48mm vs 58mm pad. There is 10mm less surface area on the inner dia. You can visually tell the differences between them by the 3.6rotor having 5/4 cast hole pattern vs the 3.3/RS which has a 4/3 hole pattern. The 3.6 can be used with the 3.3/RS or medium S4 caliper but the 3.3/RS rotor cannot be used with the 3.6 big red caliper.

The 928 GTS rotor is identical to the 3.6T rotor just minus the cast holes.

I had a set of alcan aluminum hats I used but they were difficult to source and when I switched over to the 993 aluminum upright I had to use the 993TT rotor offset since the upright is designed to use them only.

koenig_roland

where do i get such a combo? I would like to stick with my current setup... Brake power is brilliant... My buddies with 96GT3s, 97GT3, 91GT3 and GT4 are always laughing about my (late) brake points and the "things" i do on the brake with my old blue car...


About "softer" pads: i have some sets of pagid blue, orange and mint left.. I`ll use them and after that, i will also check other brands like dixcel, endless, haw and PFC... List price for the RS-discs is craczy. A rear disc was some years ago round about 350,-€ per disc. I have two sets now and hope they last quite long.. the front discs have been cheaper, but the price-tag increases every year... Some years ago, i paid >300,-€ for one turbo 3.6 disc at a porsche dealer.. after that, i started sourcing my brake-stuff online and was able to get some deals over the last years....

The problem is not the price itself nor the cracks.. it is the combination. If i would have a ~100,-€ solution per disc, the crack would not bother me... but with >300 per disc and cracks after one (hard) event, that`s no option... When i can have a disc-solution, that would last two or three seasons (3 up to 5 trackdays per year and some tourist-laps @ the ring), this would be fine, even when the disc is up to 500,-€....