Brake Master Cylinder upgrade

OK so a lot of you would already be aware that I'm running the front and rear Brembo calipers (with DBA4000 slotted rotors) from an R33 GT-R on Sillbeer (couple of pics here). Unfortunately the model of Silvia I've used as a base rolled out of the Nissan factory without ABS. Now this wouldn't seem like such a problem, but then I need to be able to fill these massive calipers (in comparison to the stock) ones with decent pressure and the stock Silvia brake master cylinder (BMC) just would not be up to the task with a resulting deep pedal. The other problem being that non-ABS cars need three ports on the BMC, 1 for the rear circuit and two for the front circuit. In the Nissan line up there's little choice in the larger sized BMC's available.

So the hunt was on for a larger BMC. Now there's quite a number of articles from the USA that says that their Z32 300ZX NA version did come up with a 1" (BM50) and 1 1/16" (BM55) BMC, and has been used successfully on their S13 240SX cars with larger caliper kits...so that was the first direction I took. After looking at a number of the photos of this setup, it finally clicked that this just wouldn't work...they drive on the left hand side of the car...so the ports on the BMC are on the wrong side. This was backed up by the fact that Nissan Australia couldn't find anything in their parts database for an Australia equivalent. Back to the drawing board.

After a couple of weeks, another light blinked on at the end of the tunnel. I recalled that the R32 GT-R N1 came from the factory without ABS fitted. Now the N1 came in two basic versions. The first was based on the standard GT-R, and the second as I understand it was based on the V-spec and V-spec II versions, which used the same Brembo calipers as the R33 GT-R (which I'm using). Next was to find some pics of it...and after a bit of search on the Yahoo Japan auctions, I found some and this confirmed the existance of a 1" BM50 brake master cylinder with 3 ports on it. Yay. Now it was just a matter of finding the Nissan part number. Part of the clue came from these photos with some of the part number stamped onto the end of the BMC body. The other bits came from the Nissan Fast software.

- Screen capture of GT-R Brake Master Cylinders

Relavent Translations:
(5) #46010-05U01 | *RB26DETT.GT-R.17 | Tokico 1" N1 Specification
(6) #46010-05U21 | *RB26DETT.GT-R.17 | Nabco 1" N1 Specification

After confirming that there were two numbers matching my requirements, a call to Northside Nissan in Perth confirmed their availability - which was affirmative ex-Japan. Pricing was reasonable at around $530 retail and about $450 trade. When we ordered, it wasn't sure which item of the above two would come in, but in the end we go the Tokico unit (46010-05U01). Here's the pics below of the brake master cylinder now all hooked up.

R32 GT-R N1 Brake Master Cylinder Pics:
- Part number on front
- Outside view - BM50 | Nissan | Tokico
- Outside view closeup
- 3-ports overhead shot

So for all those doing big brake conversions on your Nissan Silvia or Skylines which didn't have ABS, or you're wanting to remove the ABS, then this would seem to be the solution. Of course there's the subject of brake bias that is still to be tested, but that's all par for the course.

Cheers
Brendan

PS> Thanks to some of the boys in the Japan sub forum on Skylines Australia for your Japanese-to-English translation help.