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HalM
Just got my new to me 914 back from my wrench. I had him go over it with a fine tooth comb not only for Tech Inspection, and a coupe of known issues, but I wanted a really good idea of what I had bought a few months ago. Turns out, the car is in excellent health except for a couple of known rust spots that I will have repaired in July.

One of the concerns I had before taking it to him were the brakes. I guess I am just too used to my wife's 993 and the memory of my recently sold SC. The 914 just didn't feel like it had any serious stopping power. My wrench changed the fluid and did a detailed inspection of the pads, rotors and calipers. His evaluation is that they are normal 914 brakes.

So moving to SC brakes would seem to be the obvious choice. But that is a lot of money when you add in spindles, suspension parts, wheel and tires. What about a 320 brake conversion? How good are these conversions? And if I do 3-5 DE's per year in the car, would I be happy in the long run with them?

Any other options out there I am not thinking about?

Thanks for any and all help on this.
PeeGreen 914
I'd post this in the "garage" as you will get more feedback on it. I know of people that do that upgrade, but they say it is just okay. Really you should remove the proportioning valve and get better pads. That will help alot. Pagid Orange or Porterfields are what I like. Then you should save to do the 911 setup. You will like that for many reasons...eg, more wheels available, better brakes, and more.
Eric_Shea
QUOTE
His evaluation is that they are normal 914 brakes.


...not buying that. Put some Porterfield pads in those "normal" 914 brakes and see what that does for you.

BMW "upgrades" aren't.
Eric_Shea
QUOTE
Really you should remove the proportioning valve


I would "never" do that to a stock 914 brake system.
PeeGreen 914
Why? I was told to do it by a tech that knows 914 very well, but it may be because I have the 911 fronts. I know you are the brake guru so please educate me biggrin.gif
SirAndy
QUOTE(Eric_Shea @ Jun 28 2007, 05:07 PM) *

QUOTE
Really you should remove the proportioning valve


I would "never" do that to a stock 914 brake system.


agree.gif stock brakes front/rear and *no* prop valve is a recipe for disaster ...

and like eric said, the BMW "upgrade" isn't ...

play with different pads first, if that doesn't get you where you want to be, save for some later model 911 brakes.
but like you said, then you'll need the whole lot. axles, struts, rotors, calipers, wheels, tires, yada yada yada ....

having said all that, my '84 carrera brakes with vented rotors (front/back) have *plenty* of stoppage!
bye1.gif Andy
grantsfo
Make sure calipers are in good shape, use high quality brake fluid, Porterfield pads and you'll have more than enough stoppage power.

I could lock up sticky DOT tires at any speed with stock setup.
PeeGreen 914
Back when I had the stock setup with Porterfields I too could lock em up. Have them bled properly and use those.

So, back to my question... Why do you remove the proportioning valve when you change to the SC set up?
SirAndy
QUOTE(Blood red 914-6gt @ Jun 28 2007, 09:05 PM) *

Why do you remove the proportioning valve when you change to the SC set up?


simple:

because with the bigger brakes, the front/back bias is off.
when i first installed the carrera brakes on all 4 corners, i still had the stock prop valve.
the rear brakes didn't do anything and the front brakes had to do all the work.
replaced the prop valve with a "T" and now the balance is perfect.
the fronts lock up just a tad before the rears.


if you have stock brakes front/rear and you replace the prop valve with a "T",
your rear brakes will lock up *first*.
which results in you losing control of the car and spinning.
not good.

stirthepot.gif Andy
PeeGreen 914
Oh, I get it now. I was thinking that may have been the reason, but that would have just been a guess. Thanks for clearing that up for me biggrin.gif
Eric_Shea
QUOTE
please educate me


Andy did a great job. wink.gif

I'm using S-Calipers up front and 914-6/GT calipers in the rear. I'm going to keep the proportioning valve in my car and playing with the setting (it's adjustable... the kind I like, set it and forget it.) It's the only progressive P-Valve that I know of and I've never seen one fail. They get a bad rap because they're sometimes difficult to bleed. I like the idea of having a progressive p-valve back there that you can adjust.
HalM
Sounds like I should try Porterfield's before I start worrying about upgrading to a SC brake system. I Googled Porterfied's and see that there are a couple of models for the 914. Which one is best for mostly street with a DE once per quarter?
grantsfo
QUOTE(HalM @ Jun 29 2007, 04:55 AM) *

Sounds like I should try Porterfield's before I start worrying about upgrading to a SC brake system. I Googled Porterfied's and see that there are a couple of models for the 914. Which one is best for mostly street with a DE once per quarter?

R4-S Model
Joe Ricard
Actually R4S for the street and Autocross and R4 for DE's

It is easy to swap pads while you change tires.
You will go through R4S pads at a pretty fast rate in a DE. So actually it is cheaper in the long run to have two different sets.

DO NOT DO THIS AT HOME
I run early stock fronts and late stock front in the rear. with a stock P valve that I adjusted and tested..... with the pads mentioned above. OMG braking. But BE CAREFULL ON THE STREET.
HalM
Thanks everyone for the help. Another noob question: Where is the p-valve located?

Hal
Joe Ricard
Where the two rear wheel brake lines join together at the fire wall.
Don't fuck with it.

When doing a brake bleed you can verify it works by having your brake pedal pusher person push real hard. when you open the bleed screw you can hear the valve shift as pressure is relieved.
HalM
Thanks Joe. The help is much appreciated.
Matt Romanowski
If you guys want some real pads for DE, then try the Raybestos pads from Porterfield. Then you'll know how good a 914 can stop.
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