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YOUR RESEARCHC4S brake upgrade
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Recommend calling them as you want the proper length studs
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Suggestion
If you go this route I�d recommend calling them as you want the proper length studs for use with the spacers.
Leading evidence: 'Recommend calling them as you want the proper length studs' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Recommend calling them as you want the proper length studs' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Replace caliper piston sizing will affect pedal feel
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Suggestion
Changing the caliper piston sizing will affect pedal feel but again, you're throwing good money away.
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Suggestion
No change for the pads, but they�ll ride just up to or perhaps a bit past the top of the rotor with the spacers.
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Suggestion
I've run the OE rotors/calipers/brake lines since day one.
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Suggestion · Original poster
I even considered doing the 997 GT3 Master Cylinder upgrade but it looks like cars with PSM will have codes set afterwards and my OCD won't allow for that.
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Suggestion · Original poster
I even considered doing the 997 GT3 Master Cylinder upgrade but it looks like cars with PSM will have codes set afterwards and my OCD won't allow for that.
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Close to needing brakes all around. I was considering jumping up to the 350mm rotors that i have seen other talk about on the forums. I am trying to figure out exactly what i need. Has anyone done this? Is it the 997 turbo rotors that i order? What about pads? I am aware that i need spacers and bolts - saw them on flee bay for 125$.
any help would be great.
I can only speak to the Turbo, but yes it is 997 T rotors. No change for the pads, but they�ll ride just up to or perhaps a bit past the top of the rotor with the spacers. I�d strongly recommend to take the opportunity to switch to caliper mounting studs before you strip the threads on the uprights, which is inevitable after 2 or 3 removals of the caliper.
The 350s really full out the wheel nicely
Not much. I just happen to be surfing forums and agree with the guys on the turbo forum that these brakes suck. Normal operation is ok, but if you need to stop quick there is little to be desired and a lot of pedal effort is needed. I figured since its already time for brakes why not upgrade to something a little bigger. Since i am already going to replace the pads and rotor all around it would only cost me a little more for spacers and bolts. Even if this only gave me a few feet of better stopping distance at 60mph it would be worth it to me. Street car only. I plan on doing some track events in the future but that is not the intent for the car. Car currently has OE Porsche pads and Rotors.
This is the first time that I’ve ever heard that the 996 C4S or turbo brakes suck. I though they were excellent when I owned a C4S.
You could always upgrade to PCCB. I think you can buy a conversion kit on Suncoast. It’s not cheap, but it should provide better brake performance.
A brief searched and i am sure you will find similar results that share my opinion. No way in hell am i spending that kinda dough for PCCB for a street car. Not needed and WAY too expensive. I am looking for an affordable upgrade. Not looking for track car braking capability.
I'm not an expert, but I have driven my C4S on a track + quite a bit of street driving, and I never once thought the brakes were lacking in any capacity. I mean, they're specced for a car with 30% (100hp) more power, so they should be overkill for a C4S. I've also read every car magazine review for the C4S I've come across and I can't remember ever seeing anyone complain about braking. To each his own though - just wanted to post here so that down the road someone isn't saying "Literally everyone on the 996 forum is saying the C4S brakes are garbage and I should upgrade".
I will agree that a lot more pedal effort is needed in this car vs other's I've driven. I initially thought this was because the car is bigger and heavier - but I learned it has nothing to do with that. Its actually the amount the brakes are assisted by the booster. Porsche apparently assist less in order to give the driver more control and more feedback through the brake pedal (which I've come to appreciate). But, if you stomp on them, you stop fast.
The only other German auto I have driven was a 1979 Leopard I mk 4 tank. The brake pedal is large enough to put both feet on. So my frame of reference might be a little skewed.
I think the brakes on my C4S are great, however, the next time I do my rotors, I am upgrading them to 350mm because reasons.
The rotors are a little more expensive, but more brakes = better.
With proper fluid and pads, and cooling ducts, I�ve found the brakes adeqate for a 550hp turbo driven briskly on track, so I can�t image they�d ever be a problem for a C4. There is zero reason you�d ever need more on public roads. No joke about the pedal effort though. I had major issues with locking up trying to adjust to a spec Miata after the Porsche.
My intent is to just make them a little better. I already ordered 997 GT3 cooling ducts, Motul RBF600 Brake fluid and intend to do the 997 turbo rotor upgrades. I suspect i will be more than happy with that. I strongly agree about the pedal effort. I even considered doing the 997 GT3 Master Cylinder upgrade but it looks like cars with PSM will have codes set afterwards and my OCD won't allow for that. Again, a little better is all i am looking for.
larger rotors will do nothing to shorten your stopping distances unless your stock brakes can't induce lockup (if thats the case, you have a mechanical problem).
You may want to have a closer look at your pads. RBF600 is a total waste for a mostly street driven car. ATE 200 is more than fine for street and occasional track use
Not going to argue the point about larger rotors, thats a no win argument. There is nothing wrong with my O.E. Porsche pads (other than they are 75% worn). Also don't see the issue in using a higher boiling point fluid when i got it for less than the price of the ATE 200. My car has nothing wrong with it. I agree with everyone on this thread as well as dozens before about the brakes work exactly as Porsche designed them too. I'm just not happy with that. I don't see any reason why upgrading would be a bad thing. Do you??
1. If you got RBF600 for less than ATE200, please provide the link
2. If you can lock up your tires, your larger rotors will not be an upgrade and add reciprocating and unsprung mass.
3. Larger rotors won't decrease your pedal effort or give you any sort of feel increase.
Not sure how to provide a link to my co-worker. He runs rally cars and is sponsored by Motul. He gets stuff a little cheaper than we can. I also don't want to turn this into an argument. You have you views. I have mine. To each his own. I will do my upgrades and be happy. If its money in the trash, then i learned a lesson.
Unfortuately the GT3 ducts aren�t really any better than the turbo ones. You need to shell out for the GT2 ducts to have a noticeable improvement. Some argue there is still no benefit unless you also modify the fender liners, cut the dust shields, etc. more like the GT2. I did notice less mushy pedal on track though without the additional mods. Cool down lap and/or Post session cool down is still vital in any case.
I'm not sure this is quite right. On the surface it makes sense, but I'd imagine that the surface area of the rotor has a benefit in terms of heat dissipation and reduction in brake fade.
great feedback! I assume that each car model can have different levels of "brake assist". It's great to know that the amount of brakes applied (pushing the brake pedal) is by design and not because there is something wrong with brakes.
You are just going to throw away money and not solve anything. I've had Brembo reps on the track in the passenger seat and they even asked me if I had aftermarket brakes. I've run the OE rotors/calipers/brake lines since day one. NEVER had an issue where the brakes were either too much or too little. The pad compound is going to give you much greater variability. I run normal Pagid street pads and the Pagid Race only pads on the track. Motul RBF 660 on the track/street. You shouldn't be boiling fluid at all.
As far as feel, that's a piston/master cylinder combo but again, you're going to throw money at it without even seeing any benefit. Unless you're storming up and down the autobahn, you'll never achieve temperatures that start to impact your braking. Brake fade is about cooling and pad compound.
Look at your tires (make and compound along with sizing) and tire pressures as that's going to give you different results and feel on the braking.
If you up the rotor size to 350, all you're doing is impacting the heat capacity of the rotor and maaaaaaaybe brake torque, not feel. Changing the caliper piston sizing will affect pedal feel but again, you're throwing good money away. Look somewhere else.
