Has anyone used the 997 gt3 master cylinder part number

997 355 910 30 with the large 27mm bore in the 996 for better pedal pressure with big brakes? normal size is 25.4 mm

Wondering if the 27mm will bolt up and fit ? Thanks

 

i have not but if you end up finding something, please post here. Where did you get those numbers?

Anyone that works in a shop or a dealership can look to see if they seem compatible?

 

So far i've found a pretty good choice of bore sizes...

23mm, 24mm, 25mm, 25.4mm,27mm and then a few combos

http://www.autopartswarehouse.com/sh...r/porsche.html

http://www.fvd.us/us/en/Porsche-0/-/..._Cylinder.html

I tend to like a firm pedal and the 27mm should offer the least pedal travel, its used for the 997 turbo/gt3 with ceramic brakes. I'm going to pull it apart today and see if it will fit, stock the 996tt/gt2 uses the 25.4mm dia. 23mm is for base 966's.

996 355 910 50 996tt 996gt2,3
997355910 30 27mm for 997 tt ceramic brakes
997355910 10 997 tt steel brakes
997 355 910 00 boxter caymen

 

i have the 997 rear caliper and yeah a bigger master could help the pedal feel for sure.

 

So what's the verdict on this? Is the 27mm 997tt/GT3 compatible with the 996tt?

 

yes heres a pic , mine all finished with 27mm

 

cool did you try it, any pedal feel difference?

 

I see you needed a adapter for the rear line.

 

yes i've actually driven it a few months now, no issues and pedal feel a lot firmer and less travel..all in all a very good swap imho

yes you must use the adapter as the later 27mm cylinder has the larger thread both front and rear, got mine at autozone, you could also get a shop to make a hardline with the correct fitting sizes as well

 

I ended up making a new line with the proper fittings on each end with a flare tool - double flare. The autozone adapter is not a simple plug and play - it requires some sanding in order to make the threads catch properly.

 

could you develop a little bit more on the sanding part? How come it doesn't fit?

 

The end of the adapter (cone-shaped) has too much smooth metal on the end before the threads begin. So, it does not allow the adapter to engage the internal (female) threads of the master cylinder in order to crush the double flare end properly.

Another poster/thread described what he had to do inorder to get it to fit.

 

Why not use a reverse flare to AN on the master and the abs block and use a braided line to fill it in? I know it is more money but I never have luck with the double flare tool.

 

I think you might be able to use the OEM line that comes on the 997GT3. They have two versions available in PET, a hard line #10 (99735531430) and a flex line #8 (99735531110). The hard line is about $60 and the flex line is $95. I'm pretty sure the flex line would work and most likely the hard line also assuming that the brake master is in the same position relative to the hydraulic unit on the 997GT3/TT as on the 996TT. To make this work, the size of the female opening the the hydraulic unit that the line would plug into would have to be the same on the 997 and 996TT. I'm going to take a look at a friends 997GT3 and see if the OEM 997 lines would work as this would be the best solution instead of using an adapter of making a custom line.

 

Good find. I am not sure as it seems they made parts changeable.. Almost. Except for one or two things.. Always something.