A couple brake questions, For you 911 conversion guys Options

[BMXerror]

Question 1: Which 911s used the 4 piston calipers? All I found on pelican for calipers were very similar to the 914-4 calipers (weaksauce).
Question 2: What in the suspension needs to be changed to go to 911 brakes? In other words, are the control arms different, or just the spindles? I know I'll have to go to five lug, but I do know what all is necessary to do that.
Question 3: What size rims do I have to run to stuff say 911 sc or turbo brakes under them?
Question 4: Any other changes I would have to do to the brake system besides calipers and rotors? I'm already running a 19mm master cylinder.
Feel free to answer any or all. Thanks for any help.
Mark D.

[Jeroen]

1: 964 (carrera 2 and 4) and later
2: you need 911 front struts and hubs, depending on what you have, you may need new balljoints
3: 15" (but notice there's quite a few more tricks to mount 911 turbo brakes to a narrow bodied car - read $$$$$)

counter-question 1
before you spend your hard earned money...
what are you expecting from bigger brakes?

[TravisNeff]

Answer 1: 964 cars and newer, 944 turbo, 928
Answer 2: You only need to swap the struts. You can swap the whol A-arm & Crossmember - but not required (you get torsion bars 1mm bigger than stock)
Answer 3: 15" wheels for SC brakes, for 911 turbo I dunno, some will fit a 15" wheels others won't - depends on the year.
Answer 4: Nothing else is required, you could remove the proportioning valve and replace it with a "T".

[BMXerror]

In response to Jeroen's question, it's not BIGGER brakes that I really care about. Cooling is my big concern. I want vented, probably drilled rotors because this thing's gonna be driven HARD. I plan on doing lots of trackdays. Also, I would like 4 piston calipers because I don't really like the feel of the brake on 914. You have to really bury your foot into it to get not very much. I would like it to grab a little bit more. As for spending my hard earned money, well, racing is expesive. I may be nuts for wanting to race on my salary, but I see more brakes as a necessity if I'm going to get some serious power (which I plan to).
Travis, a T and an internally adjustable perportioning valve are going in as soon as possible anyway. I don't really care for the brake balance under hard braking and downshifting. I've locked the rears up a couple times going into a corner which is not a comforting situation.
One more question; I don't know the 911 models from that era too well, so what years are the 964 series. Thanks to both of you for your info. It's been very helpful.
Mark D.

[VegasRacer]

Adding some sort of ducting to get cool air on the rotors does wonders to keep them working well on hard track days.

[race914]

Here's a couple of many options out there

4 piston 964 caliper kits

(IMG:http://www.vehiclecraft.com/pictures/Products/964_2_911_kit_sm.jpg)


Rotor Cooling kit

(IMG:http://www.rennsportsystems.com/brakecooling.jpg)


I have early 70s 911 T struts, vented rotors with M calipers and a cooling kit. This setup works great for track events. Haven't found a need to upgrade past the M calipers. But the Big Blacks or Big Red setups are out there.

[Jeroen]

964 (also known as Carrera 2 and Carrera 4) are 1990 through 1993 or 1994
944Turbo calipers are the same
You'll need to make some very minor changes on the mountingholes on the caliper
Use Carrera 3.2 (1984-1989) rotors

For the 911 struts, these come with a spacing for the caliper mounting bolts in 3" and 3.5"
Get the later ones 1978 through 1989 - SC or Carrera 3.2
Some earlier cars also had 3.5" spacing, but I'm not quite sure which ones... So be sure to check

I don't know your car's specs, but the 4 piston calipers may be overkill on a narrow bodied car
I'm pretty sure SC or Carrera 3.2 brakes would suffice

[DanT]

You do not have to go to 5 bolt to get vented rotors.
You will need to go to 5 bolt to get 4 piston calipers.

I did M calipers on the front with vented SC rotors using the magical mythical Billet 4 bolt front hubs.
M calipers give you plenty of braking and the vented rotors keep the brakes from fading for 30+ minute sessions. You don't need to use the brakes much on a 4 cylinder 914 (IMG:style_emoticons/default/biggrin.gif) say to yourself....momentummmmmm, momentummmmmmm (IMG:style_emoticons/default/driving.gif)
These brakes work great...with stock rear brakes and removing the bias valve and replacing it with a T.

My car is used to TT/DE and Axs. For a 4 cylinder car you just don't need that much brake. (IMG:style_emoticons/default/blink.gif)

[Eric_Shea]

Go for a ride with Joe Richards.

Pads... you can go racing on your salary and put some money in the bank.

[BMXerror]

You do not have to go to 5 bolt to get vented rotors.
You will need to go to 5 bolt to get 4 piston calipers.

I did M calipers on the front with vented SC rotors using the magical mythical Billet 4 bolt front hubs.
M calipers give you plenty of braking and the vented rotors keep the brakes from fading for 30+ minute sessions. You don't need to use the brakes much on a 4 cylinder 914 (IMG:style_emoticons/default/biggrin.gif) say to yourself....momentummmmmm, momentummmmmmm (IMG:style_emoticons/default/driving.gif)
These brakes work great...with stock rear brakes and removing the bias valve and replacing it with a T.

My car is used to TT/DE and Axs. For a 4 cylinder car you just don't need that much brake. (IMG:style_emoticons/default/blink.gif)

I'm all in agreement with you when it comes to the 1.7 that I'm running right now, but I'm planning to build a 230ish HP big type 4 later on, and I'm gonna want some serious brake for that. More speed on the straits = more time slowing down = more heat. As for the 4 piston calipers, like I say, I just don't dig how they feel. Besides, I can always have less brake with less foot. Thanks all for you comments. This helped a ton!
Mark D.

[John]

In response to Jeroen's question, it's not BIGGER brakes that I really care about. Cooling is my big concern. I want vented, probably drilled rotors because this thing's gonna be driven HARD. I plan on doing lots of trackdays. Also, I would like 4 piston calipers because I don't really like the feel of the brake on 914. You have to really bury your foot into it to get not very much. I would like it to grab a little bit more. As for spending my hard earned money, well, racing is expesive. I may be nuts for wanting to race on my salary, but I see more brakes as a necessity if I'm going to get some serious power (which I plan to).
Travis, a T and an internally adjustable perportioning valve are going in as soon as possible anyway. I don't really care for the brake balance under hard braking and downshifting. I've locked the rears up a couple times going into a corner which is not a comforting situation.
One more question; I don't know the 911 models from that era too well, so what years are the 964 series. Thanks to both of you for your info. It's been very helpful.
Mark D.

How many drivers will this car have (at the same track event)?

In all honesty, you probably haven't driven a 914 with properly working stock brakes. The stock brakes, in good woring order, are capable of locking up the front wheels at will.

Heat capacity of the stock rotors is not so great, but again, properly functioning brakes with high performance pads will do well.

In my honest opinion, the most you will need would be 911 SC brakes all around (vented rotors and 911 calipers)

We (my dad and I) share a track car and typically drive it back to back with one of us in the instructor group and the other in the most advanced student group. We drive the car HARD and it held up well with 911SC fronts and 914 front calipers in the back for years with no problems.

A couple years ago, we changed the fronts to 930 units, but the main difference is that the pads last longer as they are bigger. The 930 calipers weigh much less, but the rotors weigh much more.

If you don't like the feel of stock brakes, plan on a minimum of a 23mm master cylinder with 4 piston calipers or the pedal travel will be enormous.

We are switching our rear calipers out with 911 SC rears. (The rotors are less expensive and vented).


I still stand with my opinion that you should need no more than 911SC brakes (in all four corners) and then you would need my yet to be released 911 e-brake conversion parts.......