khooni

I'd be the first to admit that driving on the street is a much less intense affair for me than on track. AS such, confidence on the brakes is less of an issue (when you get used to it). on a back to back run between the spyder and the CR, you will immediately feel the softness and the increased travel described. Because fade is not an issue on the street, the adjustment on confidence is just something to get used to. The car will stop and is tyre traction limited anyway. The difference is the longer and linear travel allows one to heel toe even if you are not coming from big stops. I can do it for the PCCB spyder too but it requires much more finesse not to be jerky and the window for a good heel toe is much smaller. In other words, if you think a good heel toe is a satisfying way to drive, imo, the steels make this easier.

With a rock hard pedal, how do you heel toe unless you run PDKs.......


Now then comes the question of dead initial travel. I don't think so. It is simply a longer travel because the stopping power is linear. what differentiates a dead initial travel is huge stopping power after the initial deadness, the steels aren't like that, they are progressive from start to end. In the same vein, I hate sport mode because of the compression of the power band.

I understand a lot of folks don't have the luxury of running cars that have the 2 different systems so you can judge what is best for you but it does require a bit of assessment that may require time driving.

I deliberated for a long time what i preferred. On track, the PCCBs are unparalleled (ie Joe, PCCBs are the best thing since sliced bread for you), the travel although shorter is still linear and allows for great heel toe and superb trail braking. The steels offer the same but the onset of fade is something you have to grabble with and the confidence; it just isn't the same. I certainly don't think the steels will stop in the same distance even though I know that braking is tyre limited (when fade hasn't come in).

So, i would rather my CR have PCCBs and my spyder have steels. Or i'd just have to track the spyder more....


PS: this is my favourite topic too..............

orthojoe

I'm not sure if I'm following you here. A rock hard pedal would make it much easier to heel toe, IMO. I've said this before, but the GT3 brake pedal is rock solid for a reason.

If you're saying that a solid brake pedal makes it more difficult to heel/toe on the street, I can possibly see that since you're not hammering the brakes...

khooni

yup.. i think we are on the same page.

heel toe on street..... not hammering brakes on street driving.

zellamsee

I am still at a loss as to what may be causing my "softer" brake pedal. After a week now with the new fluid, there is no doubt in my mind that it is "mushier" than I remember. The weird thing is that the "softness" appears to be inversely proportional to the speed of the car --- that is, at slower speeds it is really soft, and at higher speeds it feels somewhat firm. I think a GT3 master cylinder is in the cards . . . .

orthojoe

The only thing I would be worried about is that you felt the brakes were perfectly fine before. Maybe it's just the pads, or maybe your mind is playing tricks on you (very easy to do once you are fixated on something that wasn't an issue before.. it's happened to all of us)

Also realize that the GT3 master cylinder is not the holy grail solution. The master cylinder will only shorten the pedal travel. The endpoint will still feel spongy, and not rock solid. I believe that this is a result of the brake system being overboosted. No solution to this problem, unfortunately.

5500

When you install the GT3 MC and bleed the brakes thoroughly, I think you'll be very satisfied with the results.
Unless your lines are afew years old, you will probably not feel a difference. Brake pads can be changed to accomodate your braking needs based on how/where you drive.
I find the stock CR pads work well on moderately driven street tired cars at DEs. Better pads will stop quicker but also generate more heat, and possibly more braking than street tires can handle at the track.

pjmachineco

Help! I recently put new rotors and pads on my Spyder

I am wondering why you had to replace your rotors?
I am on my third set of EBC pads with 15000mile and 15 track days, the rotors are still in spec.
My brakes feel mushy after a track weekend.
After bleeding, they are good as new.

zellamsee

Well, my Spyder is back at the dealer, to see if they can figure things out. At stop, my brake pedal travel is well below my gas pedal. And super mushy. That ain't right!

orthojoe

Let us know what they find!

the_vetman

OT: John, did NJMP require all cabriolets to run with the top down when you were there last? Meaning, all cabs' tops must be down even without harnesses and arm straps?

khooni

that's not right for sure.

pjmachineco

[/QUOTE][/QUOTE]OT: John, did NJMP require all cabriolets to run with the top down when you were there last? Meaning, all cabs' tops must be down even without harnesses and arm straps?
No, I was the only one running topless.

orthojoe

I'd recommend that you guys run topless if possible. The chassis flex that occurs can snap the metal bar. Take a paperclip and bend it enough times, it's going to snap.

zellamsee

Update -- my dealer inspected my rotors, pads and lines and found nothing wrong. The dealer bled the brake fluid again, and while there certainly is some improvement, the brakes are still mushy and "mushier" than I remember. What is interesting is that when the car is off, the brake pedal feel is solid as a rock. There is hardly any brake pedal travel! When the car is powered up, however, the pedal is soft and the pedal travel is long. This tells me that the master cylinder is likely working just fine. One guess is that the booster perhaps is broken, or perhaps is giving too much boost (per the factory set up). What is interesting too is that when braking from higher speeds, the pedal is actually pretty firm; when stopping at slower speeds (e.g., in local traffic, to a stop light), the pedal is mushy and the pedal travel is long. Again, perhaps this a function of the booster, and perhaps this is the factory set up. If so, why would Porsche set it up this way??!!!! Argh.

Another possibility is that the ABS on my Spyder is defective. But, that seems unlikely. I will try and trigger ABS sometime soon, to see if it works.

stevecolletti

It was the same with my Cayman R. It felt like it had to be an air leak or a bubble somewhere. After lots of bleeding (ask Alex @ Sharkwerks) and a GT3 MC, it's about 80% 'right'.

I have no idea why Porsche has decided to make the brakes so mushy. As I've written in another post, our 2000 & 2001 Boxster Ss didn't feel like that, nor did the brakes on a 92 Voyager minivan that I'd recently driven.