Bm57 master cylinder

[drifter17a]

I have changed my front to evo with alpha omega racing so it is running evo 6 caliper and big routers

 

rear is stock and all corners rebuild with red stuff pads

 

fluid is dot 4 castrol racing and braided lines all around

 

i also bought brake stopper to stop master cylinder travel 

 

i have a horrible softbrake but if pushed it will stop hard

hate the feeling though as front are 4 pot rather than 2

 

i am also looking to install evo caliper and 370z rear disc which is big brakes rear

 

i think that will make brake feel worse

 

would installing bm57 help?

 

seen various feedbacks people stating larger cylinder like bm57 makes it even softer 

 

i don’t know much about master cylinder and what brake bias i would have but looking for some advice

 

it is on r34 gtt

[GTSBoy]

9 minutes ago, drifter17a said:

seen various feedbacks people stating larger cylinder like bm57 makes it even softer

Not possible unless you f**k up the bleeding.

What do the ratios of piston areas look like, Sumitomo caliper vs Evo caliper? Surely you did this research before you bought the kit.

 

[Kinkstaah]

I went from GTT brakes to an 8 pot KSport/D2/Attakd/Clone kit. I had similar symptoms to OP.

I noticed that people who had GTR's who upgraded to the brakes I bought said they had no brake feel issues.
I noticed that people who had GTR's who upgraded to Evo brakes and they said they had no brake feel issues.

The BM57 was a night and day difference, much firmer.
I got annoyed at it for many years. Just buy a BM57.

[Robzilla32]

BM57 is the AOR recommendation for their Evo kit or at least it was when I bought it for my R32 a few years ago

[Chris32]

I did the Evo Caliper/Evo10/ Alpha Omega front conversion on my 34 over Christmas

From a few people I'd spoken to via a FB group, series 1 R34's had a BM44, and series 2 has a BM50

The BM50 has L5 cast onto it, the BM44 has L4 cast onto it

People with the BM44 had issues with the ABS not kicking in if you jumped on the brakes hard. Someone mentioned it was a volume issue

Mine with the BM50 seems to work great so far.

I had a similar issue about with a squishy pedal when I swapped to 33 brakes on my 32. I put the calipers on the wrong side, and couldn't bleed the brakes as the nipples were at the bottom Looking back that was pretty funny - check the bleed nipples are at the top

 

[Unzipped Composites]

HFM sell a BM57 master cylinder for around $150. At that price, how could you not?

[drifter17a]

Made me laugh, we all made thosr kind of mistakes

[Kinkstaah]

42 minutes ago, Unzipped Composites said:

HFM sell a BM57 master cylinder for around $150. At that price, how could you not?

BEWARE

I read bad things about the HFM one.
I also found out that Z32 BM57's are NOT the same. The knee point on the Z32 one will lock your rears much longer before they start to engage the fronts. The GTR ones are the ones you want. There's a R34 and R33 version. What's the difference between those? I have NFI. I got the R33 GTR version and the clip does work on a R34.

My R34 had nothing labelled on it's BMC, only a L6... which isn't L4 or L5!

 

[GeeDog]

6 hours ago, Kinkstaah said:

I went from GTT brakes to an 8 pot KSport/D2/Attakd/Clone kit. I had similar symptoms to OP.

I noticed that people who had GTR's who upgraded to the brakes I bought said they had no brake feel issues.
I noticed that people who had GTR's who upgraded to Evo brakes and they said they had no brake feel issues.

The BM57 was a night and day difference, much firmer.
I got annoyed at it for many years. Just buy a BM57.

Exactly the same here but on a GTST R33 - same front brakes, same soft pedal, same years of annoyance - the BM57 made a huge difference.

[drifter17a]

Is ut a straight fit or requires mods?

[Unzipped Composites]

3 hours ago, Kinkstaah said:

BEWARE

I read bad things about the HFM one.

I searched around and saw a few posts to this extent, but it was always reference to having read bad things, I never actually found a post written by someone who had a bad experience and what the issues were. There's a few good reviews on their website, not that those carry a lot of weight.

 

We'll find out anyway, I've ordered one for my car. Figured it was worth a punt.

[KiwiRS4T]

2 hours ago, drifter17a said:

Is ut a straight fit or requires mods?

Just bolts in but check that your booster is working properly as well.

[Kinkstaah]

2 hours ago, Unzipped Composites said:

I searched around and saw a few posts to this extent, but it was always reference to having read bad things, I never actually found a post written by someone who had a bad experience and what the issues were. There's a few good reviews on their website, not that those carry a lot of weight.

 

We'll find out anyway, I've ordered one for my car. Figured it was worth a punt.

The only thing I found from it (other than "I heard it was bad") was that it had the same bias as a Z32 BM57, which holds 50/50 split much longer (double) than a GTR one which splits to 60/40 much earlier.

In other words, expect more rear bias with the HFM/Z32 BM57. Doubt anyone would notice it unless you tried both back to back in different cars though.

[drifter17a]

I bought one for nissan genuine one

 

will fit in and report back

[Unzipped Composites]

22 hours ago, Kinkstaah said:

The only thing I found from it (other than "I heard it was bad") was that it had the same bias as a Z32 BM57, which holds 50/50 split much longer (double) than a GTR one which splits to 60/40 much earlier.

In other words, expect more rear bias with the HFM/Z32 BM57. Doubt anyone would notice it unless you tried both back to back in different cars though.

If that is the only issue, then it isn't exactly an issue and more just something to be aware of and have in your mind if you get rear brake lock ups. Realistically, there's no saying standard distribution is more suited to a car than more rear bias. There's so many things affecting that, so standard bias on a modified S-chassis isn't necessarily the best anyway.

 

I would consider leaking and poor fitment as issues to beware of, but I shall endeavour to report back on this once the car hits the track again. If it's not poor quality, then it may still be a very good cheap option.

[niZmO_Man]

I bought that HFM one a few years ago. Took like a year to put them on, the rears never got any fluid = junk.

Still stuck with factory one for now.

[drifter17a]

I bought the nissan genuine one

 

what car was bm57 initially deployed on?

[KiwiRS4T]

6 hours ago, drifter17a said:

I bought the nissan genuine one

 

what car was bm57 initially deployed on?

R34 GTR, some Zeds not sure which.

[drifter17a]

Sorry for noob questions but what is zed?

as z32 etc?

[drifter17a]

Has anyone here fitted the alpha omega evo caliper with 370z disc at rear?

 

would it allow custom tension rod and arm to be installed ? When I asked alpha they said they guarantee it works on Standard car