FTS

Finally, I got brake cooling done right; went to Piper Motorsports explained that I was overheating the brakes at certain tracks and we divised a good plan. At last VIR event, things worked out so much better than before, consistent pedal pressure without worries; here are few pics that Piper guys took during fabrication and installtion:

Dave DE

It looks like a very clean solution - I like it! Were there any mods needed to the splash shield behind the rotor?

thanks
Dave

TAch Miami

That looks pretty good.

Did you see this thread about using the GT3 brake cooling ducts? https://rennlist.com/forums/987-forum/372823-brake-cooling-duct-upgrade.html

FTS

The dust covers behind the rotors were not modified except drilling of two holes for attaching a piece fabricated to channel the air into the rotors.

Yes, I know about that solution, which has not been enough for me. I need the air directed into the rotor and vented out of rotor's vains.

smlporsche

VEEERY nice!
Let me ask a dumb question...What exactly did they do? i.e. how much is from your car and how much was fabricated?
Are you using a 2 or 3" hose?
Do you have any pictures of it mounted on your car?

FTS

Eddie:

They re-used the stock no-purpose front plastic center plastic piece per my request, so the intake pieces behind it had to be fabricated to fit its curveture. Then, I did not want to remove the rotor's dust shield which covers 3/4 of the rotor surface, so they had to fabricate a piece that would attach to the dust shield that is light, durable to heat and cold, not to mention that it would actually get the air into to the rotors from the center and push air out of the rotor's inner venting veins. I think they used some sort of PVC-silicon something. I wish had more pics, but alas.

I thought, for my needs, 2" hose would be sufficient and fitment would be easier, but they thought 3" would work much better, so 3" went in. They had a lot of routing issues to figure out; apparently right under the nose of the CS is very crowded, unlike a 911; they mostly work with 911s, this was the first on a Cayman for this type of work, there are some detail differences apparently.

JR944

Resurrecting this old thread to ask "So, how has it been working?"

I'm currently trying to help a friend with his Cayman S. The car has GT3 Cup scoops, but still burns through pads very quickly, probably 4:1 front vs. rear using the same compound pads. Brakes feel ok, at least until the pad gets pretty thin. The car also has a third radiator installed, so a fix like this one is not possible.

It is perhaps blasphemous on this forum to say, but I think the brakes on the Cayman S (particularly the '09 with even more power than the earlier versions) are just barely adequate for hard track use. Like the 964 and 993 (particularly the C4 versions), I'm afraid that pad must just be changed earlier and higher wear rates expected. Compared to a 996, I believe the Cayman S has basically the same size front pads and rotors yet is a platform that does not utilize the rear brakes to the extent a 911 can.

Any suggestions, comments, observations would be appreciated.

Joe

FTS

The cooling has been working very well for me from a performance perspective. The consistency of brakes lap after lap (even with 18-20 laps in a single session) has been very high independent of pads I have used. I have been using Hawk HT-10s and DTC-60s; both compounds are very good, although the HT-10s have a little better torque in my experience regardless of what the brochures say. Wear of my pad haven't changed much, a set of front pads last me 2 1/2 events; however, that is an improvement because my driving has also improved significantly compared to the times before the cooling; about 2-3 secs/lap at Summit and 5-6 secs/lap at VIR.

I would imagine that the PFC rotors also have a lot of contribution about the performance of the brakes, they were installed at the same time, however, I believe the consistency of the brake performance is primarily due to cooling, which helps increase my confidence of course.

Overall, I don't think I can authoritatively answer the question of if the stock brakes are adequate for the car; I haven't felt they were not before, but I cannot compare of other Porsches, as I have no experience with 996s or 997s.

ChrisF

FT: have you always used the Hawks or have you ever used Pagids? Do you race or do you just do HPDE's?

FTS

I never used Pagids, too expensive for me, but I tried Porterfields, which did not work out at all; I only do DEs.

Krokodil

JR944,

Something seems funky. I race a Cayman S with no real cooling (worn down GT3 ducts only), stock rotors, and Pagid RS-29s and wear the fronts and rears at an almost identical rate. In fact, I have, at times, cooked the rears and discolored the calipers. I also wear out a set of rotors per set of Pagids. This is all pre-wing BTW.

What suspension is on the car? It is possible, that with stock springs and ride height (plus style) that the driver is just getting the car on its nose too abruptly and not allowing the rears to work. This may be aggravated if there is not enough rear tire or lack of proper camber/toe control under braking contributing to reduced grip.

Alternately, the driver may not be getting into the brakes hard enough to get the rears to work and is overheating the fronts by riding the brake too long.

Finally, he may just have a cocked up F/R brake bias. I have no idea how to check or adjust, but I am sure someone here knows.

Cheers,

UberXY

I agree with Krokodil. I roadraced SCCA/SVRA for 15 years and never had a brake overheating problem on any car, including 12 hour endurance races that required a brake pad change at 6 hours. And some of the cars had braking systems from the 1960's.

JR944

Thanks for your thoughts Krokodil. Sorry I'm just getting back to you now.

The car has GT3 Cup cooling fins on the front. Pagid black pads front and rear, fully set up as a race car with Motons. I don't recall the spring rates, but have driven the car and it's pretty neutral. Brakes feel just fine to me.

The owner is a skilled and experienced driver running very respectable lap times.

My friend is going to TWS next week. We're going to pull the nose when he returns and see if we can route some cooling ducts from the front of the car. I'm looking at the round running lights and thinking they are almost the right size and are sitting in a relatively high pressure area.

In the meantime, I'm just encouraging him to replace the front pads a bit earlier than he would have on his old car (1978 Euro SC, E class PCA race car which is currently for sale BTW). My standard rule of thumb is to replace when the friction material is roughly the thickness of the backer plate. I think if my friend pulls them before they get that thin, he'll be fine.

The brake bias has not been messed-with. I can't imagine how it could be anything other than the factory ratio.

After 2 days at High Plains Raceway (CO) and 4 at Sebring He's about 1/3 of the way into his third set of Pagid Blacks and I just replaced the rears this week, before necessary, just so he wouldn't have to mess with them at TWS. Based on the degree of heat checking, the front rotors will be about due for a change after TWS too.

What year is your car? Are you running stock weight or is the car lightened?

Thanks!
Joe

Krokodil

Joe,

Great information. It certainly appears not to be setup or driver talent.

As I understand it, Sebring is tough on brakes (no personal experience). I chatted with pro-level driver earlier in the week after he co-drove one of the Interseries Caymans at Sebring and he also commented on brake temp and wear at that track.

Also, while the blacks should hadle the temps better w/o fading they will wear much faster than the yellows (why they handle the heat). Maybe try the yellows?

My car is now lightened (2920# w/ driver), but I raced it all last year (17 sprint races) at 3220# on two sets of RS29s. That said, really only a couple of our tracks are hard on brakes (Laguna Seca).

Finally, the fog light holes are in the wrong spot for use as an air inlet as they are dead in the middle of the radiator (may be able to make it work?). The lower inside of the radiator inlet will make a better duct location as it aligns with an opening at the lower inside base of the raditor mounts (need modification to make room).

Let us know how what you find.

Cheers,

astoddard

Krokodil,

I am also having problems with brake overheating, specifically it seems that my rear brakes are getting hotter than the front as evidenced by the caliper discoloration. This sounds similar to the problems you were having. Did you add any additional cooling/ducting to mitigate this?

I would like to find something like this for the Cayman:

http://www.suncoastparts.com/product...3BRAKEUPGRADES