PorschePhD

David,
Change your brake lines to the normal DOT stuff and that will go away.

Dknebes

Stephen,

I thought the stainless lines made the brakes pedal feel harder. Are you sugesting I change back to original brake lines? Why would the stainless lines make the brakes feel as if they need to be bled.

David

PorschePhD

No, they will make it feel as suggested. The inner liner is different on those hoses. By switching back to a DOT hose you will find that the pedal is firmer. Most of the SS lines on the cars out there are not DOT approved anyway. This means that they choose not to go through testing with the lines to receive DOT approval. It has been my experience for the past 13 years that the SS lines will general not leave a firm feeling pedal due to the inner hose and lining used in the SS line which is often Teflon verses the standard brake line which generally is a braided reinforced line.

Dknebes

Thanks Stephen, Do you have these in stock?

srf506

I have the teflon steel braided hoses with the stock 930 brakes. I don't track the car, but IMHO I can modulate the brakes much better with the stainless than with the DOTs. Now maybe that was because the rubber was probably original equipment on a twenty year old car. I just have a better "feel" for the amount of brake I'm using with the new lines. Before the pedal was just a rock. Then again, could just be in my head too. Sometimes when I come off my meds you know...;-)

PorschePhD

The factory lines will break down in time causing the inner hose to collapse. The pedal becomes unusually hard and sometimes will hold pressure in the caliper. This causes the caliper to drag or hang up. Porsche builds some pretty good DOT hoses.

Peter Carroll/Toronto

Be very careful mixing brake parts. You don't want to affect the brake bias. I believe S4 front with the 930 front on the rear maintains the correct bias. I don't think the big red fronts with the 930 fronts on the rear is correct. Messing up the brake bias can make the car brake poorly or cause an unexpected accident.

For example with my Brembo GTPs. I put new Pagid Blacks on the front while I used up my old Pagid Orange rear pads. Seemed like a reasonable thing to do. The next couple of weekends out, I kept locking up the front brakes unexpectedly. It felt exactly like there was oil on the track. The car was also very hard to control under high speed braking. Braking into turn 8 at Mosport, the car would dart left and right wildly. You never knew where it was going to end up.

Finally after a couple of minor and one major off track excursion at the bottom of corner 3 at Tremblant, I decided enough is enough. I put a fresh set of Blacks on the rear and the car was transformed! It was now totally stable under high speed braking. And I was able to break much deeper into corners with confidence.

Basically, the mismatched pads had moved too much brake bias to the front wheels. The rear brakes were not doing their job. The fronts were doing all the work. The rear end was wandering all over the place.

If you don't get this stuff just right, you can really hurt yourself!

Dknebes

Actually my set up with the Big Reds front and switching the fronts to the rear is common. My car Brakes at high speed with no lock up, very straight and with no twitching. I couldn’t be happier with the stopping power and no fade, I would like better feel in the pedal.

DonE

I ran this set up for about a year at Road Atlanta and VIR - worked extremely well. The only reason I went for big reds all around was that I found another set (fronts) real cheap. I had to install a bias valve, but once I set it, I haven't had to touch it again.