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Need some help from those who have upgraded their brakes...

As I've gotten a bit quicker and am asking for more and more out of the stock brakes, I'm getting fade earlier and earlier in the sessions. Sometimes it's manageable, but have had more than handful of "oh [email protected](" moments now, so it's time to do something definitive. I'm currently running stock calipers with sebro slotted rotors, motul 600 fluid, and pagid yellows (rs19). I have the gt3 brake ducts up front and the tt brake ducts in the rear. Even tried adding titanium shims, with no real benefit seen. My fluid is always less than 6 months old, and I swap pads when they get to about 50% of original thickness.

So, all that said... thinking the 996 gt3 6 piston calipers up front, but can't tell what the best way is to get these to fit... some sort of adapter (Vision Motorsports seems to sell a package) or replace knuckle / wheel carrier (Suncoast kit has this option). Or, there is a Brembro kit that has a nice looking bolt on adapter to the stock wheel carrier, but uses a different caliper design that isn't open up top, so a bit more work when I need to change pads. And of course, will need larger rotors up front too... AP rotors perhaps? OEM 997tt fit? I Not excited about the high price of girodisc... but bottom line is what will pair best with the caliper I choose?

For the rear, it's far less clear what the best call is. Options seem limited. Perhaps just a larger rotor but stick with a stock caliper? Or is there a decent larger caliper that I could make fit too? Would really prefer a larger caliper for heat dissipation, and to make sure things stay fairly balanced in terms of brake bias.

I'd like a solution that others have used, preferably without too much fabrication. "Bolt-on" would be nice... so I can DIY this... but if bending the hard lines is going to be needed, I'd prob involve my mechanic to be safe.

On, and one last issue... while my stock tims or 19s, my track wheels are 18s, so whatever I do needs to fit under that. That Suncoast kit says 19s required, but I thought I'd seen others use the 996gt3 caliper under an 18?

thanks in advance for any experience others can share!
 

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Just sounds like boiled brake fluid. Put Pagid black on the rear to move some of your braking bias aft and bleed your brakes before every track weekend. No hardware change should be needed beyond this for typical 25 min track sessions. Running 2 hr enduros is a different matter. If you think the fluid is ok but you are cooking the Yellows, switch to Raybestos ST-43 pads and gain another 400-500F operational envelope. Putting larger brakes up front will compound the problem by moving brake bias forward, putting the car on it's nose and increasing front brake heat.

Until you have exhausted your possibilities with stock brake care and feeding, leave the hardware as-is.

What tires are you running on track days? 888s?
 

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Need some help from those who have upgraded their brakes...
When I was heavy into HPDE events I installed speed bleeders into my calipers (speed bleeders are one way to make brake bleeding a one person job) and I'd bleed my brakes quickly between each session. I got to the point I could do the bleed in a little over 10 minutes (single nipple at each corner on that car).

Another tip I have is to not brake lightly (such as during a cool down lap). Hard braking converts the kinetic energy to heat more quickly causing a higher peak temperature. This allows more energy to get whisked away in the air than with a lower temperature (heat transfers more quickly the larger the temperature differential). I started realizing this when I'd find that using light braking during cool down laps I'd actually start to feel the brakes getting softer. So either no brakes during a cool down lap or full brakes despite the reduced speeds.
 

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OK,

how about my solution.. here is us changing pads.. on the big brake kits i push.. and its cheaper than Brembro... it has Titanium pistons.. which are cooler.. the pads are comparable to pagids if need be..

Seriously it took about 7 to 10 min a corner..


We have kits that fits 18" by about 5mm.

i suggest you also look into our brake fluid that i have been changing all the locals too.. Torque RT700 ..its a small company that has a great product.. not a advertizing juggernaut , but something that works and extra 15% .. and is enough extra advantage not have a bleed in the middle of track day...boiling point is 685 degrees..


and they stop..




 

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No torgue wrench for final on the lug bolts? Or was that lost in editing?

Not trying to throw stones or anything. Just lost count of the number of times that lug bolts or nuts installed with the 'factory calibrated' impact wrench had breaking torques in excess of 150 ft-lb. I got into the habit of checking when I got a car back after the wheels were removed when I had trouble removing the lug nuts/bolts at the road side with the silly little lug wrench that came with most cars a couple times.

When I got tires on the 944S2 I just took in the wheels. Figured there was a reason Porsche devoted a couple pages in the manual to removal of broken alloy lug nuts...
 

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we torque everything down at schnell with a snap on digital torque wrench that goes out for calibration testing every Febuary .. .. on every car. We probably lost it in the edit... we never ever tighten with just the impact hammer..Specially before a race..We have studs on company car.. and we do 96 lbs on the studs.. as per our stud makers specification..

Lemon
 

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This has been covered lots of times in the past, but rather than chastising you for under-using the search feature here is my 2 cents. I would say I have a lot of experience trying to keep the brakes on my car from roasting...:crazy:

1. With stock calipers/rotors, you can add cooling flow (GT3 ducts as you have done, and additional cooling via hose ducts from front), use really high temp fluid, and adjust your braking style. But depending on the tracks you drive and how aggressively you brake, eventually the stocks cannot handle it. [I did all of that and made it work for a few years, but it was a constant battle.]

2. Girodisc offers a larger rotor kit that will help some. IMO, this is a great cosmetic upgrade and a minor improvement from an ultimate braking performance standpoint, but will not ultimately solve the heat problem for an aggressive track car. Probably fine for a street car that is tracked occasionally or not pushed hard.

3. The answer is bigger brakes. It seems to me the two best front options out there are (1) Porsche GT3 conversion (Vision kit is the simplest way because it does not require changing the wheel carrier) and (2) Stop Tech. Both should work fine from a performance standpoint. Both are crazy expensive (the reason we all try to make the stock setup work). [After years of struggling, I upgraded to Stop Tech fronts this year.]

Some things to think about regarding the two BBK options:

  • Porsche GT3 calipers require removing the caliper to change pads because the bridge is fixed. Stop Techs in theory allow pad changes with the caliper in place, because they have a bolted "bridge" that can be removed. I've changed the pads once, and did it in place. Though the bridges did require some effort to remove and reinstall. For pad change convenience, neither will match the stock setup.
  • Various pad choices are available for either, but the Porsche calipers are probably more common if you ever need help in a pinch. [Translation: I needed pads during a race weekend at Buttonwillow recently, and the Stop Techs just are not that common so I was unable to find someone with spares on hand. I bet I could have found an extra set of pads for the Porsche calipers, especially since it was a PCA club race.]
If you're serious (which from the list of mods on your car it seems maybe you are), my advice is to go straight to the answer (#3 above) and save a lot of interim pain and suffering. In retrospect I wish I had.

:cheers:
 

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Thanks Lemon. Sorta guessed that from watching the care used in removing/replacing the wheel on the hub and through the process but it did rather stick out in the video.
 

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Discussion Starter #9
3. The answer is bigger brakes. It seems to me the two best front options out there are (1) Porsche GT3 conversion (Vision kit is the simplest way because it does not require changing the wheel carrier) and (2) Stop Tech. Both should work fine from a performance standpoint. Both are crazy expensive (the reason we all try to make the stock setup work). [After years of struggling, I upgraded to Stop Tech fronts this year.]

Some things to think about regarding the two BBK options:

  • Porsche GT3 calipers require removing the caliper to change pads because the bridge is fixed. Stop Techs in theory allow pad changes with the caliper in place, because they have a bolted "bridge" that can be removed. I've changed the pads once, and did it in place. Though the bridges did require some effort to remove and reinstall. For pad change convenience, neither will match the stock setup.
  • Various pad choices are available for either, but the Porsche calipers are probably more common if you ever need help in a pinch. [Translation: I needed pads during a race weekend at Buttonwillow recently, and the Stop Techs just are not that common so I was unable to find someone with spares on hand. I bet I could have found an extra set of pads for the Porsche calipers, especially since it was a PCA club race.]
If you're serious (which from the list of mods on your car it seems maybe you are), my advice is to go straight to the answer (#3 above) and save a lot of interim pain and suffering. In retrospect I wish I had.

:cheers:
Thanks. This is pretty much where I am. While I'm not that excited to spend big, the lack of confidence in my brakes is really starting to hurt me. So, I think in the end it's worth it.

Any advice for the rears? Seems there are a few options up front, but not much for the back that I see after searching around...
 
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