Bm57 master cylinder

[GTSBoy]

13 minutes ago, drifter17a said:

Sorry for noob questions but what is zed?

Any Nissan that ends in Z. 240, 260, 280, 300, 350, 370. Specifically in this case though, the Z32 TT.

12 minutes ago, drifter17a said:

would it allow custom tension rod and arm to be installed ?

Why would it not? Aftermarket arms take up the same space as any other arm.

[drifter17a]

Reason for bug brake is cosmetic really as don’t like the small discs 280 at rear

 

bought the bm57 and thinking with the rear 350mm discs should have much better brake feel

 

tunner was trying to sway me to buy gtr brembo gold which said is much better than evo brembo on breaking performance.

 

anyone has any idea whether gtr gold all round is better than evo 6 front and rear?

front it 350mm with 4 pot caliper evo 6 and rear is standard but plan to do evo 6 brembo( bought calipers) and combining it with 370z disc which is 350mm 

 

front is 350x32 and rear will be 350x20 with brake balance of 69:31

 

re b57, it came from reputable seller and has nissan logo engraved so don’t think it will be fake right?

Edited May 18, 2020 by drifter17a

[GTSBoy]

1 hour ago, drifter17a said:

Reason for bug brake is cosmetic really as don’t like the small discs 280 at rear

 

1 hour ago, drifter17a said:

tunner was trying to sway me to buy gtr brembo gold which said is much better than evo brembo on breaking performance.

Lack of compatibility of statements is concerning. Cosmetic trumps performance. So just do what you want.

1 hour ago, drifter17a said:

front is 350x32 and rear will be 350x20 with brake balance of 69:31

How do you come to that ratio? Have you done all the calcs? You have the hyradulic bias at the MC, then you have the hydraulic ratio at the calipers, courtesy of the different piston areas. Then you have the brake torque which is a calculation done off the pad force, coefficient of friction of the pads (which are not necessarily the same front & rear) and the effective working radius of the force applied to the rotor.

[drifter17a]

I agree bigger isn’t always better hence why asking for opinion

 

on ratio, it was taken off alpha omega racing website. 
 

would gtr caliper be better than evo as some tuners claim?

what is your concern? Bigger disc can mess up the ratio or performance?

[KiwiRS4T]

I'll tell you what worked for me which may or may not work for you.

BM57 M/C

Front 330mm D2 with 8 pot calipers

Rear R32GTR brakes  297x18 with twin pot Sumitomos and high temp pads.

These worked great on road and track.

I can't think of a circumstance where you would need brakes as big on the back as on the front.

[Unzipped Composites]

On 18/05/2020 at 10:14 PM, niZmO_Man said:

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.

Interesting, that is obviously a bigger issue. Did you take it up with HFM, did they help at all? 

[niZmO_Man]

nah was >12 months after purchase, didn't bother. I even bench bled it before putting it in the car.

[Unzipped Composites]

Sent them an email yesterday about it, they got back to me straight away. Said they were aware of the no fluid to rear caliper issue at the time, and it has been rectified years ago with a redesign. Also confirmed their BM57 is based on a Z32, and so may have more rear bias than a Skyline BM57 - whether this is actually an issue will depend on the setup of the individual car it's on.

 

Seem like a good company, so I'm happy to give it a go and report back. It can often be hard to shake a poor reputation through word of mouth once you've had an issue, but if they have identified problems and worked on them then that's all we can ask. If it works now, then it is a great solution for ABS and Non-ABS setups, and at a great price to boot.

[KiwiRS4T]

45 minutes ago, Unzipped Composites said:

Sent them an email yesterday about it, they got back to me straight away. Said they were aware of the no fluid to rear caliper issue at the time, and it has been rectified years ago with a redesign. Also confirmed their BM57 is based on a Z32, and so may have more rear bias than a Skyline BM57 - whether this is actually an issue will depend on the setup of the individual car it's on.

 

Seem like a good company, so I'm happy to give it a go and report back. It can often be hard to shake a poor reputation through word of mouth once you've had an issue, but if they have identified problems and worked on them then that's all we can ask. If it works now, then it is a great solution for ABS and Non-ABS setups, and at a great price to boot.

My BM57 was off an R34 GTR but I reconditioned it with a Z32 kit which contained the rod/piston and seals so I presume would have the Z32 bias. It worked fine on my Stagea which pulled up straight every time while thrashing on the track. The front pads still wore down much quicker than the rears so quite happy with the set up. Your experience could be different .

[Unzipped Composites]

I believe the proportioning is built into the body of the MC, rather than anything to do with it's operating components. In any case, I feel the OEM brake bias on a car that is far from OEM isn't necessarily the best situation anyway. I don't know much about these things, but I've got Evo 9 Brembo calipers up front with factory Z32 calipers in the back, so I feel like a bit more rear bias won't hurt.

[KiwiRS4T]

1 hour ago, Unzipped Composites said:

I believe the proportioning is built into the body of the MC, rather than anything to do with it's operating components. In any case, I feel the OEM brake bias on a car that is far from OEM isn't necessarily the best situation anyway. I don't know much about these things, but I've got Evo 9 Brembo calipers up front with factory Z32 calipers in the back, so I feel like a bit more rear bias won't hurt.

I have to confess i do not know with certainty how bias is achieved but I thought it was the spacing of the pistons/cups along the rod that determined the bias.

[GTSBoy]

24 minutes ago, KiwiRS4T said:

I have to confess i do not know with certainty how bias is achieved but I thought it was the spacing of the pistons/cups along the rod that determined the bias.

Nah. You know how the master cylinder has the main "tube" in line with the pushrod through the booster, and then there's also a second "tube" that is offset off to one side (and usually slightly lower or slightly higher than the main tube)? (See image). Well, that's where the bias is controlled. And that's why the two different BM57s in these Nissans can have two different bias curves. Becuase it comes down to springs and port locations and such.

[iruvyouskyrine]

This is of interest to me.

I recently purchased the AOR Evo Brembo kit as well. Running Evo 9 brembos front and rear. 350x20mm 370Z rear brake rotor and 350x32mm Evo X front rotor. Did heaps of research on what BMC to use and couldn't come to a conclusion. Decided to just use my stock (S15) BM50 2 port and use a double banjo bolt on the front system as I deleted ABS and made all my own brake lines.

Will report back once cars running (probably 6 months) as to what feel is like.

Thanks

[Tobz]

I’m still running the BM50 on my r34 GTT with ABS. Got the same aor setup front and rear 

its fine around town but on the track it’s hard to modulate the brake pedal... I’ll be upgrading to a genuine Nissan r34 gtr bm57 so there’s a bit more control on the track (with the bm50 it’s hard to get a good feel of what’s happening with the brakes and it’s actually quite easy to engage the abs and not notice....)

Edited July 22, 2020 by Tobz

[iruvyouskyrine]

Interesting, thanks for the feedback. When you say its hard to get a good feel what exactly do you mean? There is only a small windows between good braking and locking the brakes up? etc

Hard to describe i know but certainly curious. Thanks

[Tobz]

2 hours ago, iruvyouskyrine said:

what exactly do you mean?

Yep so I’m struggling to feel the pad bite into the rotor and then I’m struggling to feel when the brake locks and the abs is kicked in. I’m getting more feedback from the sound and feedback through the wheel, than the pedal feel. So on the track it’s hard to know what’s happening exactly 

[Samyr34]

Hi I have recently purchased a hfm57 master cylinder for my R34 gtt, does anyone know what tolerance u need to adjust the booster push rod to the master cylinder, thinking of doing it to 1mm. Or if the unit already is made to fit with the factory pre set on the standard booster 

Edited September 17, 2020 by Samyr34

[Unzipped Composites]

Haven't got that far myself so I have no idea; but flick HFM an email. They are very helpful and quick in replying, so worth asking them.