Fitment of Master Cylinder and Vacuum Booster..........

[Guest lasombra]

Hello Folks,

 

I am looking at wanting to place a master cylinder and vacuum booster from a 81-83 ZX on a 75 Z. Are there any mods that need to be done to facilitate this???

 

Any help and advice would be greatly appreciated.

 

Thanks in advance

[mas28O]

I just put on a 83zx MC and booster. If you have a 5-speed car you will have to move the clutch MC over 30mm so the booster can fit. Also the throttle brace is in the way, but this was ok because I am using a Acura Integra cable.

[denny411]

what problems,if any would there be with just swapping the master cylinder and not the booster? I`m planning to do this swap soon myself.

[zcarnut]

I am looking at wanting to place a master cylinder and vacuum booster from a 81-83 ZX on a 75 Z. Are there any mods that need to be done to facilitate this???

 

No major mods are needed when installing a ZX booster on the the '74-78 Z cars. The ZX booster must be installed upside down, but that does not affect it's operation.

 

The ZX booster has a one inch thick aluminum spacer that is not needed. This results in the booster studs (that go through the firewall) being too long so they must be cut to length with a hack saw. The ZX master cylinder works with no mods needed at all.

[mas28O]

There is no need to mount the Booster up side down. It fits just fine the right way.

[zcarnut]

The original poster is wanting to put a ZX booster in his 1975 Z (_not_ a 1972 Z).

 

So, I think a little information is needed...

 

The early (1970-73) Z’s have a different firewall bolt pattern for the brake booster than the later Z’s. Reason being that when the 2+2 version appeared in 1974 a larger diameter booster was needed for the 2+2. This larger booster also resulted in Nissan having to move the move the firewall components slightly for additional clearance and a new foot pedal mounting bracket had to be designed.

 

This larger booster has a different (larger) bolt pattern than the 240Z’s booster. Nissan elected to keep the same firewall bolt pattern even for the 1974-78 two-seater Z’s which used a smaller diameter booster than the 2+2's.

 

The 280ZX’s also used this same bolt pattern but the booster rear push rod tube is offset from the bolt centerline in a different direction than the 1974-78 booster. So, as a result you must rotate the ZX booster 180 degrees so that it lines up with the holes in the 1974-78 firewall.

 

The only way to mount the ZX booster into the early Z (1970-73) cars is by re-drilling the firewall. But this allows you to mount it without rotation.

[Pop N Wood]

Man, we picked up a ringer when zcarnut joined the board. Good info.

 

When I upgraded my 70 Z to a larger MC, I also had to reverse the hard lines at the MC. The front brakes must go to the tap with the larger reservoir. I think the early cars were switched front to back relative to the later ones.

[Guest lasombra]

Wow, I did not realize that I would learn this much........

 

Seriously, thanks, everyone for your input.......it is very appreciated.

 

I will be heading to the dealership sometime this week to get the vacuum booster and master cylinder........

 

This is the first stage of my brake upgrade, and wanted to insure that I had the right info, about using the ZX stuff, and how involved it was going to be....looks like I should be safe from the modification gremlins, at this point.

 

Once again a "thank you" to everyone who chimed in with information.

 

Sammy

75 280Z

[denny411]

Thanks for the info. That helps me out quite a bit.

 

By removing the spacer, I will be able to gain more clearance between the master cylinder and fenderwell headers. i will still use a heat shield, but I won`t have near the concerns about heat sinking the MC.

[Nismo280zEd]

So if you have a 5spd 78 280z 2+2 it would bolt right up.. or throttle brace modification is necessary?