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YOUR RESEARCH997 gt3 brake master cylinder upgrade
Leading reported evidence
Install 997 master cylinder
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Performed · outcome unconfirmed
I fitted the 997 master cylinder to my 996.2GT3, firmer brake feel, more confidence, easier to H&T.
Leading evidence: 'Install 997 master cylinder' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'same as some audi)' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Install 997 master cylinder' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suspected cause
In fact, i have a GT3 M/C waiting to go on (well it's the equivalent TRW, i think it was the same as some Audi)
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Suggestion
The MC / brake piston size ratio will be wrong if you're using the standard 4-pot calipers on the front.
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Is there any point in opting for the larger 27mm 997 gt3 brake master cylinder? I'm pretty much re-piping the whole car so bleedings not gona be an issue. I've found that trw make the part and can be bought from AUTODOC for £76 iirc. Thats if I can figure out how to bypass the registration part that brings up my c2s details.lol.
Any one done this?
The rest of the brake set up is standard btw. Atm at least
Depends what you're looking for. It will (afaik) give you a stiffer pedal / less movement for a given brake pressure.
I think you'll probably need some new pipes made up out of the m/c.
BTW, i've heard of this being done with the 996 gt3 m/c but not the 997 but i could well be wrong. In fact, i have a GT3 M/C waiting to go on (well it's the equivalent TRW, i think it was the same as some Audi)
On a quick google I get 997 results coming up first. I've always found the brakes disappointing so this is the first logical step seeing as I have the car in bits and the rest of the pipes off
Yes it can be done, as Skinny says you will get shorter pedal travel. - You will need a custom brake pipe made.
Does your car have PSM? If so it wont like the GT3 master cylinder and will constantly be in fault mode.
It can be rectified by adding a brake bias valve to reduce the flow to the rear calipers.
Hi crash. No psm. Mines an early car so it's pretty basic. Making a new pipe wouldn't be any bother at al so I'll maybe get one and give it a go. This would be the time to do it
I fitted the 997 master cylinder to my 996.2GT3, firmer brake feel, more confidence, easier to H&T. It's a known 'upgrade' for the 996GT3. I bought part number TRW PMN166
In what way do you find the brakes disappointing? If it's that they feel lifeless / wooden / need a hard shove (all common comments) then the gt3 m/c will make all these things worse.
The MC / brake piston size ratio will be wrong if you're using the standard 4-pot calipers on the front. The bigger master cylinder piston size works OK on the 6-pot calipers (more fluid needed to move all 6 pistons) but I suspect you'll just wind up with a really hard pedal that's difficult to modulate and lacks feel.
All very interesting points. I've never had any faith in the brakes but that's maybe more down to old Tyres and lack of grip.
I had just started to get the hang of heel and toe just before I took the car off the road. Had thought the master cylinder would have helped me get on with it :?:
