Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

2 Pages V  1 2 >  
Reply to this topicStart new topic
> Need more brakes?, What's the logical upgrade>
freestone
post Jul 6 2004, 09:53 AM
Post #1


Newbie
*

Group: Members
Posts: 20
Joined: 1-September 03
From: ny
Member No.: 1,102



Car currenrtly has a 2.7 engine and runs 914-6 brakes in back and SC up front.

How do I get a better brake feel? How do I add more stopping power, and is that necessary as I potentially upgrade the engine?

Has plenty of rubber.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Joe Ricard
post Jul 6 2004, 11:38 AM
Post #2


CUMONIWANNARACEU
*****

Group: Members
Posts: 6,811
Joined: 5-January 03
From: Gautier, MS
Member No.: 92



I would think you should have all the braking you may ever need. The way I see it these cars are so lite stopping is very easy. More HP does not equal need for more brakes.

Stupid questions like what do you do with your car most.
When was your last brake service.
What kind of pads are you using

Ans: Race car every weekend = get something bigger in the 4 piston caliper massive rotor and matching hydraulic system. (just throw more money at it as I have come to learn).
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
freestone
post Jul 6 2004, 11:45 AM
Post #3


Newbie
*

Group: Members
Posts: 20
Joined: 1-September 03
From: ny
Member No.: 1,102



I run the car almost exclusively on the street.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Andyrew
post Jul 6 2004, 11:47 AM
Post #4


Spooling.... Please wait
**********

Group: Members
Posts: 13,377
Joined: 20-January 03
From: Riverbank, Ca
Member No.: 172
Region Association: Northern California



If you havent got th 19mm m/c, get that.
Rebuild the calipers, get new pads..

What you have is enough. IF you wanted more, you could go 944 turbo fronts, and that would be all you would ever need.

Andrew
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
SirAndy
post Jul 6 2004, 12:16 PM
Post #5


Resident German
*************************

Group: Admin
Posts: 41,943
Joined: 21-January 03
From: Oakland, Kalifornia
Member No.: 179
Region Association: Northern California



QUOTE(freestone @ Jul 6 2004, 08:53 AM)
How do I get a better brake feel? How do I add more stopping power, and is that necessary as I potentially upgrade the engine?

here's what i did, in that order:

19 mm master cylinder
'86 carrera front brakes, vented and crossdrilled rotors, carrera calipers
'87 carrera rear brakes, vented and crossdrilled rotors, carrera calipers
replaced brake bias valve with a open "T"

braking is perfect now (IMG:style_emoticons/default/wink.gif)
Andy
User is online!Profile CardPM
Go to the top of the page
+Quote Post
SirAndy
post Jul 6 2004, 12:18 PM
Post #6


Resident German
*************************

Group: Admin
Posts: 41,943
Joined: 21-January 03
From: Oakland, Kalifornia
Member No.: 179
Region Association: Northern California



oops, forgot the pic ...

(IMG:http://www.914world.com/bbs2/uploads/post-2-1088655444.jpg)
User is online!Profile CardPM
Go to the top of the page
+Quote Post
lapuwali
post Jul 6 2004, 02:54 PM
Post #7


Not another one!
****

Group: Benefactors
Posts: 4,526
Joined: 1-March 04
From: San Mateo, CA
Member No.: 1,743



As stated, the need for braking power is mostly down to car weight and available traction. If you can lock your current tires, you have enough brake power. Any more brake power, and you're simply overwhelming your tires sooner, which does nothing for stopping ability. If you can lock them repeatedly, you have enough heat capacity to avoid fade. If you find you have to press harder and harder as you repeated come to a stop from high speeds, then you need to look into better fluid, better pads, and maybe better rotors.

You asked specifically about brake feel. If the pedal doesn't feel right to you, then it's possible you have to deal with hydraulic compatibility. If the pedal is uncomfortably "long" and/or feels squishy, then you may have a master cylinder that's too small for the calipers you're using. If the pedal is wooden and hard, then you may have a master cylinder that's too large for the calipers you're using. There's a post I made awhile back on the subject you can search for.

If you can't lock your tires no matter how hard you press the pedal, then I'd start with brake pads (find softer compound pads), and make sure the current pads aren't glazed or contaminated.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
scotty
post Jul 6 2004, 03:57 PM
Post #8


The Fun Never Stops
***

Group: Members
Posts: 773
Joined: 20-May 03
From: Portland. Oregon (SW)
Member No.: 718
Region Association: None



If you haven't replaced the rear proportioning valve, that's probably the problem... I have a 19mm MC , SC brakes up front, and have replaced the valve with a "t" -- this setup transforms the brakes (IMG:style_emoticons/default/smile.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
TimT
post Jul 6 2004, 04:07 PM
Post #9


retired
****

Group: Members
Posts: 4,033
Joined: 18-February 03
From: Wantagh, NY
Member No.: 313



My car is set up like Andy's now

QUOTE
19 mm master cylinder
'86 carrera front brakes, vented and crossdrilled rotors, carrera calipers
'87 carrera rear brakes, vented and crossdrilled rotors, carrera calipers
replaced brake bias valve with a open "T"


except that I have an adjustable bias valve for the rears.

Its taken me awhile but I think I have the front/rear balanced to a point that I can brake deep into a corner..

So since I have this more than adequate braking system sorted what would any normal person do? Leave it alone!!!

So Im installing the following:

944 Turbo Front calipers
944 Turbo rear calipers
23mm master cylinder
944T front drilled rotors
Carrera rear rotors
and a spacer to move out the front hubs so the discs will clear..

The calipers are being modified by Doug Arnao (VCI) to a true radial mount..

So now I get to climd the whole brake learning curve all over again


(IMG:style_emoticons/default/beer.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
anthony
post Jul 6 2004, 04:42 PM
Post #10


2270 club
****

Group: Benefactors
Posts: 3,107
Joined: 1-February 03
From: SF Bay Area, CA
Member No.: 218



Sometimes I think people confuse the pedal pressure required to stop a 914 with the braking system being inadequate. We don't have power assisted brakes in these cars. My 914 requires quite a bit more pedal pressure than my newer VW to make it stop on a dime. And as others have suggested, if the pads and rotors are old and glazed, then having the rotors surfaced, getting new pads, and bleeding the system works wonders.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Jeroen
post Jul 6 2004, 08:42 PM
Post #11


914 Guru
*****

Group: Members
Posts: 7,887
Joined: 24-December 02
From: The Netherlands
Member No.: 3
Region Association: Europe



Bigger brakes won't add stopping power
The modulation will be different and give you the feel of more braking power, but your actual braking distance will be the same

You only need bigger brakes when you suffer from a fading pedal (brakes overheating)
I don't think you'll run into that problem with your current brakes on the street...

cheers,

Jeroen
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
SirAndy
post Jul 6 2004, 09:00 PM
Post #12


Resident German
*************************

Group: Admin
Posts: 41,943
Joined: 21-January 03
From: Oakland, Kalifornia
Member No.: 179
Region Association: Northern California



QUOTE(Jeroen @ Jul 6 2004, 07:42 PM)
but your actual braking distance will be the same

this is NOT entirely true, of course ...
(IMG:style_emoticons/default/wink.gif) Andy
User is online!Profile CardPM
Go to the top of the page
+Quote Post
Aaron Cox
post Jul 6 2004, 09:46 PM
Post #13


Professional Lawn Dart
***************

Group: Retired Admin
Posts: 24,541
Joined: 1-February 03
From: OC
Member No.: 219
Region Association: Southern California



i have an interesting brake issue.

rebuilt m calipers up front, stock / 4 rears , pads from pelican.

i just put falken azenis sticky stick tires on, and can no longer lock up the brakes easily....

car grips the road like a mofo on crack....but stopping fees...inadequate <_<
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
SirAndy
post Jul 6 2004, 09:48 PM
Post #14


Resident German
*************************

Group: Admin
Posts: 41,943
Joined: 21-January 03
From: Oakland, Kalifornia
Member No.: 179
Region Association: Northern California



QUOTE(acox914 @ Jul 6 2004, 08:46 PM)
car grips the road like a mofo on crack....but stopping fees...inadequate <_<

welcome to the world of sticky tires! (IMG:style_emoticons/default/biggrin.gif)

now you need bigger brakes!
(IMG:style_emoticons/default/wink.gif) Andy
User is online!Profile CardPM
Go to the top of the page
+Quote Post
Aaron Cox
post Jul 6 2004, 09:50 PM
Post #15


Professional Lawn Dart
***************

Group: Retired Admin
Posts: 24,541
Joined: 1-February 03
From: OC
Member No.: 219
Region Association: Southern California



lol...huge difference betwwen 165 bike tires.

i JUST upgraded to M calipers....

volvo 240 anyone?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
skline
post Jul 6 2004, 10:34 PM
Post #16


Born to Drive
*****

Group: Members
Posts: 7,910
Joined: 26-December 02
From: Costa Mesa, CA
Member No.: 17
Region Association: Southern California



The Volvo pad is almost twice the size of the M caliper. I was a little shocked to see how small the M caliper pads actually are. What is the big deal with the M calipers? And I hear the S caliper is smaller yet with smaller pads. In fact, the 320i pads are even bigger than the M ,
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Aaron Cox
post Jul 6 2004, 10:55 PM
Post #17


Professional Lawn Dart
***************

Group: Retired Admin
Posts: 24,541
Joined: 1-February 03
From: OC
Member No.: 219
Region Association: Southern California



well if only 2/3 of the volvo pad even touches the rotor....which is better? how do you fix that?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
skline
post Jul 6 2004, 11:04 PM
Post #18


Born to Drive
*****

Group: Members
Posts: 7,910
Joined: 26-December 02
From: Costa Mesa, CA
Member No.: 17
Region Association: Southern California



That is an exageration, there is only about 1/4 inch overhand, not even close to 2/3rds.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
DrifterJay
post Jul 6 2004, 11:05 PM
Post #19


I break stuff...
***

Group: Members
Posts: 1,034
Joined: 25-May 03
From: Oceanside, California
Member No.: 737
Region Association: None



I thought you fixed that?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
skline
post Jul 6 2004, 11:18 PM
Post #20


Born to Drive
*****

Group: Members
Posts: 7,910
Joined: 26-December 02
From: Costa Mesa, CA
Member No.: 17
Region Association: Southern California



enough to run it like it is for now.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

2 Pages V  1 2 >
Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 26th December 2024 - 01:29 PM