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YOUR RESEARCHSlotted rotors for C4S?
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I put these on brand new at the end of January, ran 1 weekend at TWS and 2 sessions at ECR, and then replaced these with PFC dimpled while at the track.
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I put these on brand new at the end of January, ran 1 weekend at TWS and 2 sessions at ECR, and then replaced these with PFC dimpled while at the track.
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I ran the remaining 6 sessions that weekend PLUS 2 more full weekends (16 sessions) and a 1 day (5 session) event on the PFC with almost NO cracking at all (27 sessions total) - this is shown in the second set of pics below.
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Suggestion · Original poster
Can anyone recommend a source for reasonably priced slotted rotors for this car?
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Suggestion
Your mileage may vary depending on your car, track, speed, etc., but most folks that run serious DE days either suck up the cost of replacing OEM frequently, or move over to something else.
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Suggestion
Your mileage may vary depending on your car, track, speed, etc., but most folks that run serious DE days either suck up the cost of replacing OEM frequently, or move over to something else.
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I put these on brand new at the end of January, ran 1 weekend at TWS and 2 sessions at ECR, and then replaced these with PFC dimpled while at the track.
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I put these on brand new at the end of January, ran 1 weekend at TWS and 2 sessions at ECR, and then replaced these with PFC dimpled while at the track.
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Suggestion
Also, I should have qualified that the type of track you run contributes to rotor wear, but in general, IMO, if you can run your OEM rotors to the wear limits, you can probably go faster by braking harder and generating more heat.
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Suggestion
Also, I should have qualified that the type of track you run contributes to rotor wear, but in general, IMO, if you can run your OEM rotors to the wear limits, you can probably go faster by braking harder and generating more heat.
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Performed · outcome unconfirmed
I ran the remaining 6 sessions that weekend PLUS 2 more full weekends (16 sessions) and a 1 day (5 session) event on the PFC with almost NO cracking at all (27 sessions total) - this is shown in the second set of pics below.
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Suggestion
Your mileage may vary depending on your car, track, speed, etc., but most folks that run serious DE days either suck up the cost of replacing OEM frequently, or move over to something else.
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Measured the front rotors on my '02 C4S today and they're just under the min thickness of 32mm.
Can anyone recommend a source for reasonably priced slotted rotors for this car? By reasonable I mean about the same price as the OEM cross-drilled rotors.
TIA
You should talk to the guys at Deman Motorsport, they produce a slotted rotor that a lot of people really like. I can't speak for the product since I don't have them, but I can vouch for the company, good people. Unsure of pricing.
www.demanmotorsport.com
, ask for Rick or Joe.
Best,
Hans
I have PFC dimpled on my car ('00 C2), as there are no slotted rotor alternatives. Also, my research has determined that there are NO slotted/dimpled rotors comparably priced to OEM.
-td
Why slotted rotors? The cracks that develop around the holes in the c-d rotors bother me, even tho' they don't exceed Porsche's specs; i.e. no crack longer than 7mm, no crack that extends to the edge or between two holes. Also - the concensus is that slotted are better than drilled.
However, Porsche continues to supply c-d rotors as OEM, so who am I to argue with the whiz-kids of Stuttgart?
For track applications, the slotted rotors have better overall characteristics. And for hard core track junkies, the cross drilled are not even more cost effecitve as you crack them through long before you wear them out. The rotors cost more (don't forget you have to buy the hats) but they last 2X-3X as long.
IMO, Porsche provides them since they are sufficient in performance for the majority of Porsche owners and reduce cost substantially.
-td
Some of the fellows I track with have converted to the slotted rotors and speak volumes of how superior they are to the c-d. I am on the fence; however, once something goes wrong with my ceramics I will probably convert to the slotted rotors.
Ceramic rotors may actually have benefits from the cross drilled holes in terms of initial bite. You should do some research on this before you switch, unless you move to steel rotors, in which case slotted/dimpled will perform better.
-td
Not sure if I qualify as a "hard core" track junky, but I have 37 track days on these OEM c-d rotors and am replacing them due to reaching min thickness, not cracks.
The best prices I've seen on slotted rotors are at least 2x the cost of c-d. Not sure I'd be able to get 74 track days from a set of slotted rotors.
Maybe I'm just slow, but if yours aren't cracked, have lasted 37 track days without cracks, and are less than 1/2 of slotted, seems like you have a great experience set that says you'd be well served sticking with the OEM c/d.
I was primarily concerned that you
did
have cracks, and thus wanted to change, so I wanted to know under what circumstances they developed, but hearing your experience I have even more confidence in the OEM c/d [at least for my driving and less frequent track events].
I'd also like to pick your brain on the trackability of the C4S, since I loved mine at my recent DE, but that is another thread.
Ya know, reading back over this thread, I'm coming to the same conclusion duh! Guess I'll stick with OEMs. As noted, the cracks were pretty minor and for the most part were already there when I bought the car in '06 with about 23k miles on it - it now has 55k.
Send me a PM, I can go on for hours about the joys of this car on the track. I've driven it at Sears Point, Laguna Seca, Buttonwillow, Thunderhill, Spring Mountain, Reno-Fernley etc. Too much fun!
As for "hard core," if you are around a second/two/three off the track record for a race 996, but in your car's trim, run on R-comps or full-on slicks, have an upgraded adjustable suspension, and run in the fastest group (or instruct), then you probably qualify as hardcore in most folks books. If you run in a lower or instructed group, and use street tires, you are probably hardcore in training
[BTW, I probably got close to 37 track days last year alone, doh!]
Also, I should have qualified that the type of track you run contributes to rotor wear, but in general, IMO, if you can run your OEM rotors to the wear limits, you can probably go faster by braking harder and generating more heat. Also, if you still run OEM pads or simple "sport pads" you can go much faster by using a more aggressive compound - not necessarily a PFC-01, but maybe PFC-97 or Pagid Yellow.
An easy litmus test is to check how much heat your are generating is the white paint on your calipers that says "Porsche." If it still white or off white, then you aren't generating any braking heat. When they get to be brown, the you know you've gotten them hot
[Note the brown letters on the calipers] You need serious cooling after this point to keep from brake fade.
To give some context, with my setup, I pull max braking LongGs of almost 1.4 (1.38) and latGs of 1.61+. This will defintely tax your system over 20 minutes.
CALIPER PAINT TURNED BROWN
2.jpg
In any event, it sounds to me that, OEM may be working for you now, but I would still wager that if you are able to get 37 out of OEM, you would definitely be able to get 74 out of dimpled/slotted, as they
really do
last that long.
As for me, there is absolutely no way I could get 30
sessions
, much less 30 days on a set of front OEM cross drilled rotors. I barely get 20 sessions if I'm lucky and run during the winter! That is, I would only get a maximum of 2-3 weekends (4-6 days) out of a set of front rotors (@ 8 sessions a weekend). In fact, I would start to get cracks during the first weekend on them. Of course, rears last much longer, and I still use OEM for them.
Below are some front rotors pics. The first set are my OEM cross drilled front rotors with only 10 20-minute sessions on them (just 1weekend + 2 sessions). As you can see, there is almost
no wear
but
significant
cracking already. I put these on brand new at the end of January, ran 1 weekend at TWS and 2 sessions at ECR, and then replaced these with PFC dimpled while at the track. I ran the remaining 6 sessions that weekend PLUS 2 more full weekends (16 sessions) and a 1 day (5 session) event on the PFC with almost NO cracking at all (27 sessions total) - this is shown in the second set of pics below.
Your mileage may vary depending on your car, track, speed, etc., but most folks that run serious DE days either suck up the cost of replacing OEM frequently, or move over to something else.
-td
CROSS DRILLED - 10 SESSIONS
1.jpg
3.jpg
CROSS DRILLED - ALMOST NO WEAR ON ROTORS
2b.jpg
DIMPLED - 26 SESSIONS - VIRTUALLY NO CRACKS
4.jpg
5.jpg
I should qualify all of this with something that is quite important.
Your car is a system, and things need to operate together. If you are running street tires, then you should probably also be running OEM or sport pads. As you progress, you should upgrade in stages - but not just one component at a time.
When you upgrade tires, you should probably upgrade pads as well, and possibly rotors. Maybe even brake cooling. When you upgrade your shocks/springs, you should upgrade sway bars. Etc.
For most beginners, OEM pads with OEM rotors will be sufficient for at least a year, if not 2. When it's time to move to R-comps or slicks, you probably need better pads and rotors.
-td
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