Chosing a brake master cylinder..

[a_ahmed]

Well mine i believe was a 17/16" or 1 1/16" I forget now.... I have an unknown brake booster as it was replaced lol... and pedal has always been pretty hard although I liked it...

None the less... that aside.. my brake master is leaking.. I'll need to replace it...

I was wondering what to go with since I have 6pot front and 4pot rears.

If I'm not mistaken there are a few different choices?

1", 1" 1/16", 17/16", 15/16", 7/8"

I honestly would rather convert to two duals for front/rear and manual.... get rid of the booster... but that will take fabbing up and i want it up and running and do that down the line instaed...

This has been a prob since last year so I want to sort this out for upcoming season...

I'm pretty sure i had the NABCO 1 1/16". That's OEM right?

One of the things I hated with the brakes on the car no matter what has been feel.... It always feels disconnected in a way... and if the pedal is adjusted to be 'tight'... less play the pads grab (does that make sense?) but then it feels 'better'.... otherwise if its loosened there is play... and when you touch the pedal nothing happens and then u gradually push down and it grabs.. does that make sense? I like less sag/play/more direct feel... This is another issue all together but while im at it editing post to throw it in...

[Bumnah]

Leave it alone and drive the car.

[a_ahmed]

Leave it alone and drive the car.

^Yeah I'm with stupid the master is leaking fluid

Anyways just checked it is NABCO 300ZX master brake cylinder 1 1/16. I don't like the feel of it still... so I was wondering what to get since I need to get a replacement anyways.

[Bumnah]

Replace with another OEM 1/16 MC.

[2Fass240us]

You use "booster" and "master" interchangably, but I assume you really mean the master given the dimensional context.

Your 6-piston calipers have piston diameters of 1.63, 1.13, 1.13. What diameter are the rears?

[a_ahmed]

*Edited* I meant master is leaking while the booster was replaced with another nissan unknown one... not sure what it was taken from (gay)

[2Fass240us]

You use "booster" and "master" interchangably, but I assume you really mean the master given the dimensional context.

Your 6-piston calipers have piston diameters of 1.63, 1.13, 1.13. What diameter are the rears?

[a_ahmed]

Not sure on rear piston diameter... doesn't say on azc site either...

However they look like dynapro lug mount calipers:

http://www.wilwood.com/CaliperList.a...%20Lug%20Mount

Can either be 1" x2 or 1.38" x2 or 1.75" x2....



Fronts you know:



Booster was just something oem refurbished but i dont think it was off a 240...

lol very old pix, it was different than what the car initially came with thats all I know... but I believe there was a dif between auto and manual boosters:

[2Fass240us]

You need to find out rear piston size. Otherwise, I can't help you.

[a_ahmed]

Yeah :-/ I'm going to try to contact Dave from Arizona Z Car and see if he will give me the info.

[a_ahmed]

Just got off the phone was actually very friendly heh.

Well... 1.38" pistons in the rear on the dynapros. He suggested a 1" master ideally or 3/4" dual setup on manual brakes.

I got my answer I guess.

Front rotors 3584 3585 GT

rears are 277 plain

He sent me BP-20 pads and suggested I try E pads

[Def]

The piston size is smaller than Z32 rear calipers(1.5"), while the fronts have a very similar piston size to Z32 front calipers.

I think something like a Z31 15/16" MC with a higher rear split point would be a good choice, as you don't have a good front/rear bias with the stock split point now.


Not sure what the story is on S14 MCs are, but if one of those would fit the booster and has an external prop. valve(from what I've read on here), you could use something like a Wilwood prop. valve to kick up the pressure to the rear brakes and get better overall performance.

[a_ahmed]

thats weird... you know i have a brake bias adjuster in the rear line in the center console.. the whole point of installing it was that i was told that the rears are too much and may lock up so i kept it reduced... however it had this really weird feeling when braking.... i kept playing with this...until i actually made the rear MORE... and then the car braked better more controllably (eh?). And it definetely felt like it would stop better. This was after track days at the end of the season that I did this... so it was high speed on 'private test tracks'.... anyways but on track i reduced it as it would lock up too quick... so thats why i kept it reduced... however i learned to modulate better so.. it worked better... (no abs here).

I hope that makes sense... so if you're saying that.. then.. that makes sense...

If thats what you meant...

[Def]

Don't put a proportioning valve inline with your stock prop valve.

[a_ahmed]

eh i was fed and sold that information :-/ Ah well... sucks now but it looks cool in the console... (lol)

For now I'll probably just get a replacement mbc and call it a day....

What I should do is take it to a reputable local race shop and have them do a dual manual mbc setup with proper front/rear bias adjustment in cabin... call it a day and have a proper setup long term as opposed to a half ass thing i got in the car now :-/ I mean might as well get my money's worth...

Thanks for the advice... some good tidbits in here... I'm sure others have wondered about mbc choices as well...

Oh yeah.. for the rear when I spoke with Dave today. He said he has a billet aluminum e-brake option that's coming up. will be a hundred to two hundred bux (his estimate). Basically the machined caliper + new bracket for the rears (aka current ones but added mounting point for extra ebrake caliper).