What brake line sizes are on the GT3 master cylinder
#1
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There seem to be 2 sizes - certainly for the nuts. What are they?
Thanks
Ray
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Ray
#4
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Great!
Thanks - what does the 997 MC do? I am guessing that the brake bias changes. FWIW I am running the 350mm rear rotors...
Thanks
Ray
Thanks - what does the 997 MC do? I am guessing that the brake bias changes. FWIW I am running the 350mm rear rotors...
Thanks
Ray
#5
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I did not notice any significant changes in bias. It reduces pedal travel by quite a bit which is the main benefit...I think it feels alot better. Bore size is slightly larger at 27mm.
#6
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Here's the thread where I show how to modify the adapter to work. I used this on my 996 C2, then moved it to my 996 GT3. Works great I have done track days in both cars with it and love the results. https://rennlist.com/forums/996-foru...my-996-c2.html
#7
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Last edited by powdrhound; 09-19-2018 at 12:26 AM.
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#8
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Thanks John,
My real problem is that I want to plumb in brake pressure transducers... Was unaware of the MC upgrade. As it is, I am fine with pedal feel, not to happy with the ABS unit, but that is another story![](https://rennlist.com/forums/images/icons/icon9.gif)
Ray
My real problem is that I want to plumb in brake pressure transducers... Was unaware of the MC upgrade. As it is, I am fine with pedal feel, not to happy with the ABS unit, but that is another story
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Ray
#9
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No change in bias. The piston in the 997MC is larger (27mm vs. 25mm on the 6GT3) and the ports are both M12. You don't need to complicate things any adapters whatsoever Ray, nor do you need to fabricate a custom line. You simply need to install an OEM Boxter M12 brake line in place of the M10 GT3 one. Most people don't know that the Boxster MC uses M12 ports front and rear so the Boxster rear brake line makes this all plug and play. You can get the brake line on ebay for a few bucks or from the dealer for under $20. It's the one used on a 96-99 Boxster with ABS without PSM. You can see it here on my car, it's the green one.
Last edited by Nickshu; 09-19-2018 at 11:36 AM.
#11
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Thats incorrect. The 996 Cup uses the same master as the street car, the 25mm one with a 12/10mm port. The MC you reference above is found on the 997cup which does not have ABS.
#13
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About Boxster circuits :
Well, I can confirm with 100% that my 2001 Boxster S, (OEM) has the rear circuit outlet of the MC in M10 !
(front outlet is M12)
May be is because of PSM, as the 10mm outlet goes to the passenger side, to the PSM pump.
Well, I can confirm with 100% that my 2001 Boxster S, (OEM) has the rear circuit outlet of the MC in M10 !
(front outlet is M12)
May be is because of PSM, as the 10mm outlet goes to the passenger side, to the PSM pump.
#14
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With PSM in any case you will need to either custom make a new line with an M12 end, or use the brass adapter.
#15
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If you want a brake pressure transducer set up, I can post up pics of what I'm using. I consists of a banjo bolt set up mated to a Motec pressure transducer..