After boiling my fluid at Laguna Seca, I've decide to upgrade my brakes for better cooling (and maybe some performance). My current brakes are 993 fronts and 964 rears. The car is a 1992 C2. I'm upgrading to "big reds" all around (but they will be black) using the kits from Brembo. I'll also be attempting to squeeze some ducts to the rotors, but am not sure the wide tires will allow it.

Adrian is quite strident in his book that this could be a mistake due to the size of the brake fluid reservior. However, as my C2 has vacum assist, it does not appear that I could simply replace the existing resevior with the one from the turbo (the plumbing is different).

Has anyone made the change to big reds and not changed the reservior? Did you have problems? Can a simple swap in reservior be made by simply capping the extra nipples on the turbo/RS reservior or would a "Y" adapter need to be fabricated?

 

Not to worry! The Big Reds will not need a bigger m/c or reservoir than what you currently have. The piston sizes will be identical to what you currently have.

I hope that the bigger 2 piece 322mm rotors front and 312mm rear are part of the package?

 

Bill: Yes, the nicer rotors are part of it.

 

Hi Tom;

Not to worry,....we've done a LOT of these conversions and you'll be just fine.

Clarification,.....the larger MC is much preferred with larger calipers,...the reserviour is A-OK.

 

Dear Tom,
Sadly people do not admit their problems publicly. Not everyone runs into problems either. A huge amount depends upon how you look after your car.
The fact that many conversions have been done means nothing. A lot of GT-2s have ceramic brakes and not everyone has run into problems with them either. Just as long as you are aware that there are potential problems and you work out a way to avoid them. There is a reason that the 964s fitted with larger brake systems also were fitted with hydraulic boost brake systems and a much larger brake fluid reservoir. I exclude the C4s from this list. I am talking Turbo and Carrera 2 Turbolook, Carrera RS and Carrera Cup.
It might also be a good idea to look at the progression of the brakes systems in the 911. For example;
The 964 Carrera 2 has the same size brake master cylinder as the 911SC yet it has a 140cc larger brake fluid reservoir, why? The vacuum boost system is identical as well.
The 911 Turbos have a larger master cylinder as compared to the 911SC but the same size fluid reservoir. Why?
The 964 Carrera RS has a larger master cylinder than the Turbos, Turbo looks and the C4s. Why?
The key is to pass on the information, to find any hidden problems discovered by others.
Whether anyone takes any notice is up to each individual. Remember that brakes are a safety system.
Ciao,
Adrian
964C4

 

While I do agree that the 20.64mm m/c is on the small side. The physics of the situation indicate that if there is no current problem with Tom's brakes there will be no future problem due to hydralics because the hydraulic requirements of his current and future brakes are identical. The substance of this upgrade comes not from the calipers but rather from the larger rotors.

The usual m/c for that caliper combo is 23.8mm. The sportier models used the 25.4 for the better pedal feel, which is certainly desireable but is not necessary.

At worst Tom will want to upgrade the 964m/c to a 993, both vacuum actuated of course for better feel.

 

I have a similar set up to what Tom is proposing and IMHO the 20.64 master cylinder is too small. An upgrade to the 993 unit should be part of the conversion.
Pedal feel is important in modulating braking ( oops stating the obvious)

 

Would the conversion to the 993 master cylinder be a simple 'plug and play' swap? Looking at the PET, the parts look the same but most of the parts in the 993 brake system are 993 part numbers and not 964 part numbers.

I was a bit suprised at Laguna in the first time out with this car how different the brakes were from the 993 (even though it had 993 calipers up front).

 

The 993 master cylinder uses larger diameter brake lines, adaptors have been made by some privately.

This seems to be a commercial opportunity for an entrepeneur to make a simple adaptor fitting available.....HINT HINT

 

Digging around in my parallel Nissan universe, I came up with this caliper manufactured by the American company Stoptech:

http://www.stoptech.com/docs/ST40withdisclaimer.pdf

This caliper looks like and S4 caliper to me and uses an Porsche S4 pad. It is squeeze forged and not cast like a Brembo and also uses a unique stiffening bridge at the top of the caliper. The claim is that the caliper is twice as stiff because of these changes.

The calipers list for $500 each, somewhat more than Porsche OEM can be had for and may be a direct bolt on for an S4, although I don't know for sure.

A kit similar to the one pictured with a 332X32 mm floating disc, stainless brake lines pads and adaptor hardware costs around $2000 for my Nissan, front axel only.

The company makes a brake kit for the 993, but none for the 964. Does anyone have any experience with these calipers or kits?

 

Yep, 10mm(993) to 6mm(964) adapter was required. Only cost a few £`s though.

 

Hello Tony, We have communicated before on the adaptors you have in your car. As I recall they were bespoke units made for you correct?

If not, do you have a vendor and part number for the adaptor?

I think a 993 master cylinder would be a nice upgrade for many, if only the brake line adaptors were readily available.

 

The adaptors were bespoke units but IIRC made up from off the shelf parts.

They were fabricated courtsey of 9m in the UK. I sure they would oblige (if they can rember what they did )

 

Stoptech makes very nice product, unfortunately, as has been pointed out the only Porsche kit is for a 993. They have been promising for years to service the other models but we are all still waiting

 

I wonder if the Stoptech caliper would be a direct bolt on for some of the S4 applications done on the 964 now. If I get a Stoptech front kit for my Z, I will make a comparison to the S4's in my garage now.