996cab.com

Hi All,
after an a spin in the rain at a roundabout, I have lost confidence in my current brake setup. When I applied them, car just carried on spinning, rear wheels were still pushing. Not good.

I want to upgrade the brakes. I have done some research and found I can move from the current 318/28fr & 299/24re to 330/32fr but it seems I have to keep stock rears. I am aware fronts do most braking therefore I can appreciate why rears can be left as stock however I do know the 993RS did have 380mm fronts.

Questions
1) Does anyone know IF I can fit those 380mm kit to the 996

2) or can anyone suggest a better upgrade kit.

3) Anyone upgraded their brakes on a 996 as yet?

4) I drove a 964RS recently and its brake pedal was ROCK HARD (hardly any travel) so it required just a touch to bring the car to a holt, very very IMPRESSIVE! How can I achieve the same pedal feel on a 996?

996 C2 Cab
H & R Sports Springs with stock springs
18" light alloys )(lighter than stock Turbo alloys)
SO3 235/40fr & 285/30re (5,000 miles on tires so far but looks as new - occasional hard driver)
Stock engine - no mods yet!

Sorry guys for many questions. TIA

ben in lj

"1) Does anyone know IF I can fit those 380mm kit to the 996"

A friend of mine has done 350 mm and says nothing larger will fit without a larger rim (he has 18"s).

"2) or can anyone suggest a better upgrade kit."

There are lots of kits..

"3) Anyone upgraded their brakes on a 996 as yet?"

Yes, I upgraded to 330 mm frt and rear.

"4) I drove a 964RS recently and its brake pedal was ROCK HARD (hardly any travel) so it required just a touch to bring the car to a holt, very very IMPRESSIVE! How can I achieve the same pedal feel on a 996?"

Don't know. Despite upgrading to turbo (GT3) brakes and steel brake lines, mine sure isn't "rock hard". I've had them bled five times (the latest with the Porsche System Tester - best result was post PST) by three different shops (all highly qualified), and do not have "rock hard" (not even stock Boxster hard) brake pedal.

You're right about the fronts doing 85% of the work. However, I wanted the red calipers to go with it so upped em both. Also, I messed up and didn't get the floating rotors. If I had it to do over again, I wouldn't. But, if I did do it again, I'd leave the rears stock (unless you want the brake rotors to fill the open space visually) and get 350 mms w/ floating rotors on the front.

As for stopping power, once the slack is taken up on the pedal, I don't notice too much diff. I suppose the largest benefit is that the brakes don't fade owing to better heat disappation (however, you will NOT experience this diff on the street - no matter HOW you drive on the street). That said, it "seems" the ABS comes on earlier and longer. My "theory" is that the add'l braking power is overwhelming the available grip on the tires sooner. Turbos have much bigger contact patches (tires) to utilize the add'l braking forces.

Oh yeah, and my car has coilovers (lowered about 1") so the suspension is taut enough to utilize the braking forces without roll or dive which negates more abrupt weight transfer found in the cushy stock suspension. And my car is a cab too! So, the suspension, weight transfer, extra weight, etc of my car is a good proxy for yours.

ben in lj

Also something kinda wierd. After the PST bleed, the PSM and ABS lights would come on after a couple minutes of driving (even without using the brakes). Upon turning the car off briefly and restarting, they disappeared. That happened twice, and has now stopped. It "seems" the pedal (while still not "rock hard" or even stock Boxster - non S - firm) is firmer post idiot light cessation?

996cab.com

Thanks Ben,
I also want RED calipers so I would change the rear calipers ONLY and leave the rest intact.

I am definitely changing the fronts to larger disc - 355mm. I take you poing on-baord inregards to the floating points.

Thanks yet again.

ben in lj

You can have the calipers painted or just buy the rear Box S calipers. Those rear calipers should be well less than $600 new.

eclou

Don't waste your time and money unless you just want neater looking big reds.

I really doubt any variation of upgrades is going to prevent what you did from happening again. You could spend $$$ on hardware before realizing that braking TECHNIQUE is what is going to make the difference.

The stock 996 calipers are plenty good for your car unless you are going to spend alot of time on road courses and tracks that require alot of high speed braking.

If I were you I would invest a few pounds on a road driving course or auto-x. Spend a few weekends and try to go especially when it is raining. You will learn alot about the car and its capabilities which are going to be far above the driving skills of all but the most experienced track driver.

Good luck!

Eugene

ben in lj

That is a good point. MORE stopping power to just lock the wheels up sooner isn't going to keep you spinning in the rain under the conditions you mentioned - it's just going to accelerate it :-) BTW, ABS should have taken care of that in the rain anyway. He's also right in that you probably won't see much (if any) diff on the street using street tires (and pads). In fact, all I noticed was that I think my ABS is coming on sooner (grip exceeded on tires - the weakest link - earlier) since the braking power is increased.

996cab.com

eclou, hmmm.
you have a valid point. Just been speaking to a neighbour who is also a traffic cop. he shares your point and placed more importance on advance driving course - with emphasis on recovering from lose of traction. certainly interesting and cost effective financialy and limbs!

I think I would try the course first.

Questio for you eclou
what about pedal travel? won't a harder pedal be more effective and if so how do I get same feel in my stock brake systems?

ben in lj

"what about pedal travel? won't a harder pedal be more effective and if so how do I get same feel in my stock brake systems?"

Yes, and no. For example, the Boxster kind of has an "on/off" brake pedal (while being quite firm). It's more difficult to regulate the amount of brake pressure applied.

eclou

The Porsche has a pretty firm pedal to begin with, alot stiffer than other cars. If you want to firm up the pedal some more the things to try are:

1)stainless steel brake lines- resist expansion of rubber brake lines during hard repeated braking

2)quality DOT 5 brake fluid like ATE Super Blue and a good brake fluid flush - brake fluid absorbs moisture over time and also needs to be flushed every 2 years or so or yearly if the car is run at the track

3)quality brake pads such as Hawk HPS or Porterfield R4S -usually have a more aggressive "initial bite" and lower dusting than stock

These are pretty simple and cost effective mods to try first. Remember the stock Brembo made brakes are about the best spec'ed for any manufactured car.

Eugene

ben in lj

Using steel lines and ATE super blue. Don't know about the pad brand since they came with the brake kit.

eclou

There is no easier pad to change than on a Porsche. On my M3 i have to remove the entire caliper to change pads. On the Porsche just the anti-rattle clips and bingo!

Stock Porsche pads are reportedly very good. However I run Pagid Orange on the track and Hawk HPS on the street. I have the big blacks (993TT) on my M3 and my wife has the stock 996 1 piece units.

Eugene

996cab.com

eclou & ben,
just though you bought may be interested in further developments. Ihave revisited the scene of the accident and found there was oil on the right lane approach to the roundabout! I have always stayed in the left lane however on the day of the accident I was in the right lane. Because it was dark I did not notice the oil.

So after much soul searching I am glad to say that perhaps the brakes deserve more credit than I gave it that day. Further more, damage was only to one rear wheel. Suspension and bodywork escaped unscatthed!

Ben,
would PSM have helped? I am considering an '02 C2 Cab with PSM. WHat is your take on PSM - I know you have them on your Cab. Could it have saved me in such scenario?

ben in lj

Hard to say if PSM would have helped, but it sure might have. PSM can brake one, two, three, or four wheels at a time among other amazing feats.

I have it and don't think I'd want one without it (for street stuff like you mentioned).

996cab.com

ben,
thanks for that.