OntarioMark

After completing a considerable amount of suspension work, I am thinking next about upgrading brakes. Probably a project for the winter, but I nonetheless want to get an early start on considering options. If I stay with 16 inch wheels, I see three options at the moment: 930 Turbo brakes, Brembo GTP Lightweight or Paragon's 911 Front Big Brake Kit which utilizes 4 piston Boxster aluminum monoblock calipers. Thoughts?

Perhaps related is the issue of wheel size. At the recent Mosport Club Race I saw that at least one of the fast 911s in F-class appeared to be running 18 inch wheels. I know the bigger wheels would open up a range of brake options, but I kind of like running the 16s (I like the looks, I have 3 sets of 16 inch wheels, and the tires are a little less expensive.) Am I going to be handicapped staying with the 16s?

sjanes

Don't bother with the Boxster calipers since it uses the stock rotor. BTDT. I have 993 fronts (requires 17" wheels) and 930 rears which ended up giving me too much front brake bias, but 930 front/rear (if you can find them) would be better balanced. No experience with the Brembo GTP kit but I've heard good things about them.

Do you race the car? Wouldn't big brakes move you up a class?

smlporsche

I have a slightly diferent car but run 16" wheels as well. I did the 930 front brake upgrade and am very happy with the increase in braking performance.

rickdm

I have the 930 front rotors with a 928 S4 caliper, which is the same as the 993 caliper, and a bit larger than the 930 caliper. This works with a 16x7 wheel with a spacer, and works with a 16x8 wheel without a spacer. On the back I have the 930 caliper and a brake bias adjuster. I have always assumed that if I went club racing I would have to get rid of the brakes to stay in class, but I have never checked.

sjanes

I was told the S4 caliper required a 17" wheel (which I had anyway). Interesting to know it also works on 16".

What type of brake bias adjuster are you using? I have one on my rear circuit, it's fully open and I still have too much front bias.

Bill Verburg

for 16" wheels either a full oem 930 modified for 911 trailing arms, GTP-L, or the new Zuffenhaus 917 style kits shown below are the way to go


You can put together a DIY form 993(or 928 S4) parts w/ 930 rotors but it's a sort of frustrating process, yes, it works w/ some 16" wheels, best are aftermarkets like BBS or Fikse but 944 Fuchs work too.

OntarioMark

Do you race the car? Wouldn't big brakes move you up a class?[/QUOTE]

I will be racing the car. My understanding is that an 88 3.2 runs in E class, but if "Prepared" such that it moves up one class to F, the brakes are essentially free. My car, given some other modifications already made to it, would be considered prepared and would run in F.

earlyapex

I have 930 front and rear calipers.

Rennsport Systems sells a kit and can get you what you need. Give Steve Weiner a ring.

http://rennsportsystems.com/

OntarioMark

Eric,

Steve is on my list to call when I get closer to making the purchase. I purchased custom valved Bilsteins from him and he did a very good job with them.

How do you find the rotors hold up in terms of wear?

Bill Verburg

The heart of any BBK is going to be the rotors

the Boxster kits use the small 3.2 Carrera rotors, not much of a gain from SC rotors

oem 930 from '78-80 used 304x32 Brembo floating rotors, these are what you want on your race car. They are available through the dealer channels or from Pro-Systems

Here is a Pro-Systems floating mock up


The Zuffinhausen kit also uses these rotors(I believe that they offer plain or slotted too), the Zuffinhausen kit also has the advatage of bolting on to the 3" 911 trailing arms and is available w/ a lighter rear rotor for race use only if you want to omit the parking brake.

The GT-L kit also has good rotors they are a little smaller & lighter than the 930s but still more than adequate for a 3000# SC/Carrera

OntarioMark

Bill,

I am will look into that Zuffinhausen kit as well. Is that the name of the manufacturer such that I Google the name and will find it, or do you have a specific supplier you would recommend I speak to?

Mark

Sean F

Holy guacamole that Zuffenhaus kit is sweet!

sparks259

i have early 993 fronts, same pad size as a 930. but have had to use coleman rotors.
on the rear, i have 944turbo fronts, with 930 rear rotors.
i also have a rear brake proportioning valve.

chrisp

Are big brakes on a 3.2 going to reduce lap times much? Enough to justify the expense and extra weight?

Bill Verburg

Info on the Zuffenhaus 917 kit here