GT3 Master Cylinder install in a Cayman R
03-30-2013, 05:39 PM
#1
GT3 Master Cylinder install in a Cayman R
I've been meaning to get this done for a while. It took me about 3 hours to complete with my 3yr old son helping me, so it will probably take you about 2 hours to complete. The brake pedal travel on the CaymanR is crazy long (especially on the track). After this modification, braking is instant and the pedal is rock hard just as my RS. I bought the GT3 master cylinder ("MC") http://www.ecstuning.com/Porsche-201...der/ES2539327/, (buy the TRW unit (they build the MC for Porsche), exactly the same as oem Porsche (I bought both to confirm) only difference is OEM unit comes in a Porsche parts box, and save yourself $140) a new set of stainless brake lines http://www.ecstuning.com/Porsche-201...nes/ES2581673/ and a few bottles of new fluid http://www.ecstuning.com/Porsche-201...uid/ES1931452/ to bleed the system after installation from ECS Tuning. I decided to replace the oem brake lines with stainless lines (since I would have the fluid drained anyway) and install new Pagid RS29s at the same time. Checkout the pics below.
Steps:
0. place the car on a lift or on jack stands and remove the wheels;
1. Open the frunk and remove the 7 torx screws holding the front plastic cowling, disconnect the carpet tab and frunk light connection to get access to the MC;
2. Drain the brake fluid at one of the calipers (I choose the passenger side rear caliper to remove as much of the brake fluid as possible) using the motive http://www.ecstuning.com/Porsche-201...ing/ES1895871/ bleeder (whole system fluid will fit in one of the motive catch bottles);
3. Place a rag under the MC to catch any dripping brake fluid as you begin to remove the oem MC;
4. Remove the two lines running from the ABS unit to the MC;
5. Remove the plastic reservoir by twisting it side to side (not front to rear), to remove from the MC (no mechanical fasteners holding it place);
6. Loosen the two nuts holding the MC to the brake booster (do not remove the two blue bolts in the middle of the nuts that hold the booster to the fire wall);
7. Remove the MC from the brake booster by pulling and twisting gently to release any residual vacuum. Be careful to not spill any residual brake fluid on the car while removing;
8. Install the new MC in the brake booster (be sure the piston in the brake booster aligns with the sleeve of the new MC), secure with nuts, reattach the abs lines and plastic reservoir;
9. Fill the reservoir with new brake fluid of choice, put the remainder of that 500ml fluid bottle plus one more 500ml bottle of fluid in the Motive bleeder unit and proceed to bleed the brakes at both bleed valves on all four calipers;
10. If the brake pedal is still mushy after you used the Motive bleeder, have someone help you bleed the lines again the old fashion way (them pressing the brake pedal while you open the bleeders). I found the Motive unit 15-20psi pressure wasn't enough to get all the air out of the lines;
11. Reinstall the wheels, torque to spec and test drive the car. Find a safe area to engage the ABS 5-6 times to get the air out of the abs unit;
12. Then return home and remove the wheels and bleed the brakes again to remove any residual air released from the abs activation; finally
13. Reinstall the wheels, torque to spec, wash your car and revel in the fact that you just saved yourself the $500 a Porsche dealer would have charged you for the 4 hours of labor to install your new MC which now gives your Cayman the same brake pedal feel as a GT3.
Steps:
0. place the car on a lift or on jack stands and remove the wheels;
1. Open the frunk and remove the 7 torx screws holding the front plastic cowling, disconnect the carpet tab and frunk light connection to get access to the MC;
2. Drain the brake fluid at one of the calipers (I choose the passenger side rear caliper to remove as much of the brake fluid as possible) using the motive http://www.ecstuning.com/Porsche-201...ing/ES1895871/ bleeder (whole system fluid will fit in one of the motive catch bottles);
3. Place a rag under the MC to catch any dripping brake fluid as you begin to remove the oem MC;
4. Remove the two lines running from the ABS unit to the MC;
5. Remove the plastic reservoir by twisting it side to side (not front to rear), to remove from the MC (no mechanical fasteners holding it place);
6. Loosen the two nuts holding the MC to the brake booster (do not remove the two blue bolts in the middle of the nuts that hold the booster to the fire wall);
7. Remove the MC from the brake booster by pulling and twisting gently to release any residual vacuum. Be careful to not spill any residual brake fluid on the car while removing;
8. Install the new MC in the brake booster (be sure the piston in the brake booster aligns with the sleeve of the new MC), secure with nuts, reattach the abs lines and plastic reservoir;
9. Fill the reservoir with new brake fluid of choice, put the remainder of that 500ml fluid bottle plus one more 500ml bottle of fluid in the Motive bleeder unit and proceed to bleed the brakes at both bleed valves on all four calipers;
10. If the brake pedal is still mushy after you used the Motive bleeder, have someone help you bleed the lines again the old fashion way (them pressing the brake pedal while you open the bleeders). I found the Motive unit 15-20psi pressure wasn't enough to get all the air out of the lines;
11. Reinstall the wheels, torque to spec and test drive the car. Find a safe area to engage the ABS 5-6 times to get the air out of the abs unit;
12. Then return home and remove the wheels and bleed the brakes again to remove any residual air released from the abs activation; finally
13. Reinstall the wheels, torque to spec, wash your car and revel in the fact that you just saved yourself the $500 a Porsche dealer would have charged you for the 4 hours of labor to install your new MC which now gives your Cayman the same brake pedal feel as a GT3.
03-30-2013, 06:48 PM
#2
Nordschleife Master
Nice post, man! I always love posts about how cruddy the stock brake pedal is on our cars.
I find it interesting that your pedal feels just as good as a GT3 now. In my car, the pedal travel was shortened, but it still did not have a rock solid endpoint like a GT3 or any other good brake pedal. I can think of 3 reasons why our outcomes were not the same:
1). I have PCCB calipers, and maybe their larger size is still too much for the slightly larger GT3 master cylinder to make the pedal feel totally solid. Whereas you have the standard sized brake calipers, and the jump from standard MC to GT3 is what it needs. The PCCB master cylinder size is in-between, and some with standard brakes use the PCCB master cylinder instead of the GT3. IIRC, savyboy did the GT3 master cylinder mod on his PCCB spyder and still didn't think it was perfect. Perhaps another 'problem' with getting PCCB. I'm never getting PCCB again.
2). Brake pads. You are using pagid RS29 yellows. I've been using stock pagid p40 pads on my PCCB rotors (no choice). Brake pads can firm up the pedal. I will put this to the test after
I swap my PCCB rotors for brembo type 3 steels and start running PFC08 pads. I really hope my pedal will firm up.
3). I still have air in my lines. I use the motiv power bleeder, but I've never done a traditional 2 person bleed job. I may have to try this too. I do remember having a tough time getting all the air out of the system when I did the install on my car 2 years ago. I also did the SS brake lines at the same time
I find it interesting that your pedal feels just as good as a GT3 now. In my car, the pedal travel was shortened, but it still did not have a rock solid endpoint like a GT3 or any other good brake pedal. I can think of 3 reasons why our outcomes were not the same:
1). I have PCCB calipers, and maybe their larger size is still too much for the slightly larger GT3 master cylinder to make the pedal feel totally solid. Whereas you have the standard sized brake calipers, and the jump from standard MC to GT3 is what it needs. The PCCB master cylinder size is in-between, and some with standard brakes use the PCCB master cylinder instead of the GT3. IIRC, savyboy did the GT3 master cylinder mod on his PCCB spyder and still didn't think it was perfect. Perhaps another 'problem' with getting PCCB. I'm never getting PCCB again.
2). Brake pads. You are using pagid RS29 yellows. I've been using stock pagid p40 pads on my PCCB rotors (no choice). Brake pads can firm up the pedal. I will put this to the test after
I swap my PCCB rotors for brembo type 3 steels and start running PFC08 pads. I really hope my pedal will firm up.
3). I still have air in my lines. I use the motiv power bleeder, but I've never done a traditional 2 person bleed job. I may have to try this too. I do remember having a tough time getting all the air out of the system when I did the install on my car 2 years ago. I also did the SS brake lines at the same time
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browncf (10-10-2020)
03-31-2013, 04:11 PM
#3
Nordschleife Master
Scratch #3. Just enlisted the help of my wife to bleed the lines using the traditional 2 person method. Pedal still feels the same. Still hoping the PFC08 pads will help.
03-31-2013, 04:33 PM
#5
Three Wheelin'
Joe,
After this last set of mods with Alex, my brake pedal is now fairly firm, and much, much more consistent... not quite GT3, but a lot closer than it has ever been.
I've wondered all along if somewhere there was a slow leak in the brake system since (before this) the pedal would get worse over time. I wish I knew what is different.
Did you finish the brake swap?
4forme, nicely done and documented. Thank you!
After this last set of mods with Alex, my brake pedal is now fairly firm, and much, much more consistent... not quite GT3, but a lot closer than it has ever been.
I've wondered all along if somewhere there was a slow leak in the brake system since (before this) the pedal would get worse over time. I wish I knew what is different.
Did you finish the brake swap?
4forme, nicely done and documented. Thank you!
03-31-2013, 08:10 PM
#7
Instructor
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Great write-up, makes me want to do the same with my MC although I haven't had any real complaints with pedal feel or braking strength. The pedal in 4forme's Cayman R really does feel fantastic, especially after the two-man bleeding which is critical if you've drained the whole system. Motive Bleeder is good for fluid flush, but the old-fashioned way develops MUCH more pressure to get every drop of air out.
I think I'll add it to the list of stuff I probably shouldn't do but will anyway...
I think I'll add it to the list of stuff I probably shouldn't do but will anyway...
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03-31-2013, 08:53 PM
#8
Nordschleife Master
Great write-up, makes me want to do the same with my MC although I haven't had any real complaints with pedal feel or braking strength. The pedal in 4forme's Cayman R really does feel fantastic, especially after the two-man bleeding which is critical if you've drained the whole system. Motive Bleeder is good for fluid flush, but the old-fashioned way develops MUCH more pressure to get every drop of air out.
hmmm... maybe the problem is I did a one man/one woman bleed, when I needed a 2-man bleed....
03-31-2013, 09:09 PM
#9
Rennlist Member
Joe -
The new brakes are awesome! They felt great at Sonoma on Friday and definitely firmer. After feeling a firmer pedal it made me think about brake pad thickness. The RS19's are 18mm thick so I think that also may influence the initial firmness. Now I need to get used to applying enough pressure but not too much to have the ABS take over.
With the increased camber, front and rear, the car felt like it was on rails. And I must say, the Trofeo's definitely get my vote! Look forward to seeing you on the 19th. I will be there on both the 18th and 19th.
Phil
The new brakes are awesome! They felt great at Sonoma on Friday and definitely firmer. After feeling a firmer pedal it made me think about brake pad thickness. The RS19's are 18mm thick so I think that also may influence the initial firmness. Now I need to get used to applying enough pressure but not too much to have the ABS take over.
With the increased camber, front and rear, the car felt like it was on rails. And I must say, the Trofeo's definitely get my vote! Look forward to seeing you on the 19th. I will be there on both the 18th and 19th.
Phil
03-31-2013, 09:53 PM
#11
Nordschleife Master
Looking forward to seeing everyone soon!
