Marti

vanster

My 86.5 has the upgrade and I fully agree. This upgrade along with GTS "blacks" it inspires confidence that I never experienced before.

928S MN

I also understand, for the racing crowd, that you can use this 60 Bar.

965 355 305 02 60 bar (a later Porsche Turbo part number)

The Forgotten On

My 81 has 33 bar bias valves from the factory along with 993 calipers I added and it feels much better to use the brakes in than my 89 which still has the 18 bar valve in it.

Even without ABS I can stop my 81 much sooner than my 89 and in a much more controllable fashion to boot.

Marti

vanster

I have learned that getting too much bias in the rear could cause a bit a drama in the rain (wet) depending on your braking style. Something to think about.

AO

I just added a 55 bar valve to the Coke car, replacing the 33 that was in there. I have run 2 season on the same set of rear pads while going through about 5 sets of fronts. Granted this is track driving which is different than street. I just need to wait for the snow to melt so I can give it a test drive to see if I like the new setup.

UKKid35

That is weird, as I am now using up fronts and rears at roughly the same rate with a 33 fitted

This is with a mix of track and road - although the track is solely Nurburgring which is not particularly hard on brakes

The road element does include both the Alps and the Pyrenees, not sure whether that makes a difference

Marti

AO

My driving is exclusively on-track with this car and it is primarily threshold braking. But I was just given some advice to NOT use the 55bar on track as 75%-80% of your braking is done up front due to weight transfer (Duh!). So increasing the rear bias may actually reduce the threshold at which once can apply brakes (due to the rears having a tendency to lock up). This makes a lot of sense. And then there is the issue with trail braking, which I hadn't considered.

So I may opt to go back to the 33bar valve. Need to take it out for a spin to see how it "feels". Unfortunately there are still several inches of snow on the ground, so I need to wait no matter.

UKKid35

On my recent trip to the Ring I started with a cold tyre pressure of 28 psi all round

This resulted in a hot tyre pressure of 36 psi, all round, perhaps this is too high but it seems to work for me with AD08R

Rear wheels became as hot to the touch as the fronts, so perhaps this means I have exactly the right brake balance now

It was pretty warm so ambient temps reached a high of 29C late in the day

Kevin in Atlanta

Is this a 33bar bias valve?

76FJ55

Yes that is the 33 Bar bias valve.