Brakes - stay stock or upgrade?

[TriGem2k]

Just making it clear for everyone so they don't go buying both front and then find out the rears wont fit.

[Lil bastard]

It's a falacy that more power requires bigger brakes.

More power will get you 0-60 faster, but the car is still going to stop in the same distance from 60 (or any other speed) as before. The Boxster brakes are some of the best in the business and are more than sufficient for any modding a DIYer would do short of doing a lot of track or auto-x work. People are either misinformed, or they simply like the peacock effect of larger brakes, drilled and slotted rotors, etc.

If you substantially increase the weight, say by 500 or more lbs. then bigger brakes may be in order to maintain the same stopping distance.

[JackG]

Originally Posted by Lil bastard

It's a falacy that more power requires bigger brakes.

Blanket statements like that are rarely true. In the Boxster's case, the brakes are already about as good as they get for its normal performance use, like DE or AX.

However, it's a fact that more horsepower on the track will provide higher entry speeds into the corners. With higher entry speeds, you will need more braking to haul the car down to the speed the corner requires. Even if you brake earlier, you'll still be requiring the brakes to absorb more energy. If they are already near their limits, adding more horsepower *will* overcome your brake's capabilities. Brake fade will result.

In that case, it would be a trueism that "More power requires bigger brakes."

[Topless]

Originally Posted by JackG

Blanket statements like that are rarely true. In the Boxster's case, the brakes are already about as good as they get for its normal performance use, like DE or AX.

However, it's a fact that more horsepower on the track will provide higher entry speeds into the corners. With higher entry speeds, you will need more braking to haul the car down to the speed the corner requires. Even if you brake earlier, you'll still be requiring the brakes to absorb more energy. If they are already near their limits, adding more horsepower *will* overcome your brake's capabilities. Brake fade will result.

In that case, it would be a trueism that "More power requires bigger brakes."

Confirmed.

Stopping distance is mostly a function of weight and tire grip. If you want to stop faster, drop some car weight or add some fat sticky tires or both. A stock base Boxster already has a shorter stopping distance than a Ferrari 575 Maranello. It's no slouch to be sure.

Brake pad/rotor fade and overheat is mostly a function of weight, driving style and brake components. If you often overheat your brakes something is probably wrong: sticking caliper, lost cooling ducts, poor braking technique etc. Find the problem and fix it for 1/20th the cost of all new upgraded brake components.

Spongy, imprecise brake feel at the end of a long track session on a hot day is most likely brake fluid approaching it's boiling point. A well known Porsche problem. This is often misdiagnosed as brake pad fade. If you do a lot of track days just use a good high temp brake fluid and change it once a year.

If you add a bunch of horsepower should you upgrade your brake components? Maybe. For spirited street driving it is probably still overkill. If you are a fire breathing track hound the answer is probably yes.

For example: An 80hp 914 enters turn one at Streets of Willow at around 90mph. My 200hp 986 enters the same turn at 115mph. A well known 295hp 987S enters at 125mph. The 987S is carrying greater speeds into each turn and weighs a little more. He needs to scrub a lot more energy every turn and is more likely to overheat his brakes. The larger 987S brakes are matched to his higher corner entry speeds and higher heat generated.

So if you track you car a lot and drop in a 3.6L motor, bigger brake components are probably in your future. Otherwise you will probably never notice the difference between well maintained stock brakes and "upgraded" brakes... Except perhaps for that all important "Peacock" factor.

[23109VC]

no need for bling.

I just want OEM stuff. I"ll probably order OEM rotors from pelican.

I did a quick check on tirerack, because I'm also buying new tires, and noticed I can get rotors/pads from them. They sell Brembo rotors for about what OEM rotors cost.

Brembo is a big name brand, but is it as good as OEM? better?

I'll probably skip any cross drilled/slotted stuff and jsut get regular rotors.

I have seen the posts here saying I *can* put 987 pads/rotors on the FRONT. are they any lighter than stock? the only benefit I can see to going with them would be if they were ligthter.... if they are bigger it's probably more weight and I don't think I need/want that.

any recommendations on pads for street use?

[944boy]

Brembos are excellent. Equal or better than OEM depending on who supplied that particular model.

For stock pads I highly recommend Hawk HPS. Good up to light track duty, long life, quiet. Tirerack has them for a good price.

[23109VC]

so the brembo rotors are as good as OEM or better?

if I order those, plus the Hawk pads that tire rack has - i can just order ALL the stuff I need in one shot.

rotors, pads, and my tires.

although I'm not sure if tire rack sells the sensors or other little parts i might need for a brake job.... my wear light came on and someone said if the light comes on youneed to redo the sensors..

can I resuse all the other components..or are there any little pieces/parts I need to order along with rotors/pads?

I just went on the tirerack website and noted those Hawk HPS pads indicate they do NOT have cutout for the wear sensor...so does that mean you just leave the sensor off totally and forgoe using it? does the sensor light go off or stay lit up all the time?

if i want to retain teh wear sensor and have agood pad, what do you reocmmend..

maybe i'm just right back to OEM stuff.. pelican parts here i come

[Kirk]

Originally Posted by Lil bastard

It's a falacy that more power requires bigger brakes.

Bleh! I took my Boxster S for a spirited drive this weekend and the brakes performed wonderfully. I could not imagine though having the weak brakes from my Honduh CRX on the Boxster. There is NO WAY I could have enjoyed the car as much with weak brakes like that. It's all about balance - matching the engine performance with appropriate suspension tuning and braking performance. With my Boxster those performance limits are pretty high and I need brakes to match them. I guess I could have driven it okay with the weak CRX brakes, but I would have had to use half of the available power.

Likewise my weak CRX brakes are okay for that car as it's barely even pushing 100 HP and only has to stop 1850 lbs, but even then they are maybe marginal. I already have a full suspension in the CRX (roll cage, bracing, torsion bars, springs, adjustable shocks, etc.). If I added 200 more horsepower, no weight, and left the brakes the same I'd have to throttle it back and either still drive it the same as I do now or end up dead from overrunning the brakes....

Just for grins... here's my CRX daily driver:



Kirk

[Lil bastard]

It's about weight, or more specifically momentum. Adding power does increase momentum, but only if you use the right foot. A 3000 lb. car with X brake setup will stop in X feet from X Speed. If that same car gets a more powerful engine, it will get to X speed faster than before, but the rest of the variables remain the same.

If tracking the car, where the brakes are applied more fully, and frequently, the larger brakes are an improvement because they shed heat faster and so don't fade as soon. But on the street, where's there's rarely seconds between brake applications, enough time exists between braking for the brakes to cool and not fade.

Don't forget, the difference in stopping distance between the 'S' brakes and Base brakes is only 4' @ 60MPH. Could that 4' make the difference in some rare circumstance? Of course. But that's an endless debate, what if the needed improvement was 5'? Than neither brake setup would have an advantage over the other (for street).

[944boy]

Also remember, the biggest factor in braking is tires, not the brakes. Braking performance is quoted with stock tires and the base model has narrow tiny front tires compared to the 'S'. In my 987 the ABS activates rather quickly because the 205 Conti's have very little grip compared to an 235 Azenis. I could put on much bigger brakes but without better tires or less weight it's not going to stop any quicker.

[heyjae]

I can only speak for the S since that is what I have, but on the street the biggest improvement to braking will be tires. The stock brakes are more than adequate to bring you to a stop and will easily overwhelm the gripping ability of the tires. Whether you go with the OEM pad or aftermarket pad is really more about brake dust and cost. I've used OEM and street compounds from Pagid, Hawk, PBR (cheap) and they all work great on the street with differences in dust and initial bite mainly. I liked the Hawk best all around. (I thought it was the Performance Friction at first, but realized I used them as a track pad. I like Pagids better for the track.)

With rotors, I've used OEM and Zimmerman. The only difference is the coating on the hat for the Zimmerman sucks, so you'll want to to recoat it with hi temp paint unless you don't mind rust. Currently, I'm using Zimmerman rotors, which are cross drilled since I have an S. They are about 2-3 years old with about 20 track days. They've held up really well.

The equation is very different on the track. It's about repeated stopping ability. That's where bigger rotors, cross drilling/slotting, hi temp brake fluid, exotic pads, bigger brakes, etc. become more important to dissipate heat to prevent fade and fluid boiling and maintaining consistency. Adding bigger/grippier tires stresses brakes and so does adding horsepower (because you'll be entering the braking zone faster) and, frankly, just being a better driver (because you'll be entering the braking zone faster .

That said, I'm still using the OEM brakes with Zimmerman OEM placement rotors, ATE fluid and Pagid RS-14 pads (full race compound) with great success. Generally, I "catch up" to others on braking. I was at Buttonwillow yesterday and the only cars out braking me were a GT3 RS with PCCB and a Radical. This was coming from a long straight downshifting from 5th (127 mph) to 2nd (45 mph) (of course they were entering much faster than me). My brakes were solid all day even with doubled up sessions of 40-50 minutes at a time.

I will switch to 2 piece rotors when I need to replace my current rotors--for lower weight mainly and better heat dissipation. I'll keep the existing calipers. If I did an engine swap and picked up another 80 HP, I would likely go with bigger brakes.

I guess my point is that Porsche brakes are fantastic and the mid-engine layout of the Boxster seems to accentuate it further. Spend the money on suspension if you want to go faster. BTW, I was only .3 seconds off the GT3 RS on a track layout that favored high HP cars.

[23109VC]

couple of quick questions

I've priced full OEM parts on pelican for my boxster brakes vs. zimmerman and "oem supplier" textar pads.

all OEM genuine porsche = $950
zimmerman + textar = $750

I also ordered 4 brakes sensors, a motive bleeder, and fluid. essentially it's a $200 savings to get zimmerman rotors and textar pads.

for street driving - am I goign to notice any difference in these two options in terms of stopping power?

also - if I get the zimmerman rotors and want to PAINT the hats - do I just get the caliper paint / hi temp stuff at the local pep boys? do you brush it on or get spray and mask off the braking surfaces? do you guys use a gray color, black? what??

i don't mind painting 4 hats to save $200. i can spray them and let them dry overnight, then install the following day.

the dealer wants $1600 to do it for me. they offered me 10% off..so say about $1450 parts+ labor. all OEM stuff.

if I did all OEM parts, i'd be at $1000. 450 labor seems kind of high. if they woudl come down to 1200 i might bite and just let them do it... half of me wants to do it for teh "Fun" and half of me doesn't want to spend the time or get dirty.

i have to take the car in anyway for the vacuum leak...

they also do tires/alignments while it's there and I need that too. they are goin to get me bad this time.. i need that too...