Mr. C4

I have been offered a pair of front Euro RS calipers with only 45,000km use for USD 350.- which I think is a bargain. Yes, I know the discs will cost me more!!!

The question is if these calipers simply just bolt on to the 964 C4 wheel carrier or do I have to source an adapter? Any advice is appreciated!

Ciao,

Johannes
<img border="0" alt="[burnout]" title="" src="graemlins/burnout.gif" />

Cupcar

You will need an adaptor or Turbo uprights. <img border="0" alt="[typing]" title="" src="graemlins/yltype.gif" />

Adrian

Dear Johannes,
What benefit do you expect to get by bolting on RS callipers to the front of a C4. I would save your money to be quite honest.
Ciao,
Adrian
911C4

Bill Gregory

Johannes,

As Cupcar mentioned, you will need an adaptor for each caliper (assuming you keep your existing struts), which, for FVD adaptors for example, run around $250+ per pair. The Euro RS calipers use a 322x32mm rotor, and S4-sized pads (not big red sized but larger than 964). Since I happen to have one handy, here's a picture comparing the 964 front pad with the S4 pad:

<img src="http://members.rennlist.com/sansho/pads1.jpg" alt=" - " />

S4 pads have about 45% larger pad area than 964 fronts.

You would want to go to larger calipers if you track your 964, to gain additional heat sink capacity from thicker/larger rotors and larger pads. With larger front calipers and stock rear, you may find the front/rear braking balance is off, but there are ways to deal with that. You may need 17" wheels with the RS calipers, too.

For price comparison, new RS front calipers, discounted thru Porsche are under $300 each, and the RS rotors are under $200 each.

Mr. C4

Adrian,

Lets just say that I have driven a 964 with RS brakes and experienced the differance in heat/fade resistance. I have also covered a lot of mileage in 993s, which I believe has the same brake set-up as the 964 RS and they are clearly superior when it comes to heat/fade resistance.

Ciao,

Johannes E.

Bill Gregory

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica"><strong>I have also covered a lot of mileage in 993s, which I believe has the same brake set-up as the 964 RS </strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Johannes,

They are very close. The 964 RS uses a 322mm rotor while the 993 uses a 302mm rotor. Both are 32mm wide. They do use the same pad and have the same piston sizes in front. In the rear, the 993 C2 caliper has the same piston sizes as the RS, while the 993 C4 has the same piston sizes as the 964 C4. The 993 has a 40 bar bias valve where the RS uses a 55 bar valve. And the RS has a hydraulic-based system while the 993 C2 is vacuum-based (993 C4 is hydraulic-based).

Bill Verburg

If you only install the RS calipers and rotors front you will have changed the bias much more to the front.

To restore a more natural bias(for a 911/964) you should also use 993 C2 or C2s rear 30/34 calipers w/ your stock rear rotors or even better get some 965 rear 30/34 calipers for the 28mm thick 965 rotors

Also w/ any of these changes you will probably want to remove or at the very least use a much less agressive p/v

Bill Gregory

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica"><strong>even better get some 965 rear 30/34 calipers for the 28mm thick 965 rotors</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">According to VCI, the 965 rear rotors have the wrong offset for 964 usage.

Bill Verburg

Bill, I forgot that little fact. The 993 C2 rear is the only option then.