Zed Head

Here's a start. An A31 060 001 from a 1975 280Z, I think. Kind of looks like a Bosch part number on the board, but it says OHMIC. 1 288 310 011 with a big 7444 beside it.

Seems reasonable. The ZX's used a different ECU also. I wonder if the circuit boards inside might be the same. Something we can compare without too much trouble. Probably have numbers.

I meant the hole that the fluid passes through when the piston pressurizes it. Not clear (to me) what plunger you're describing. Sounds like you had already taken it apart, unless you work really fast. Here's the link to the site's file collection area. Lots of good things in there. Clickable menu on the right side. https://www.classiczcars.com/files/

The sig only shows up to other people if they're signed in. Guess I missed it, I read the posts and only sign in if I want to say something. Seems like you might just have a piece of seal stuck in your rear orifice. Ha ha. Couldn't resist. But it seems possible, based on the picture, below. That would give front pressure only. This picture is from the 1970 FSM, available from the site's Download area. Pretty easy to remove the MC and look around. The MC is easy to take apart also.

Yes, the bolt pattern is a known thing. MSA mentions it, and shows the other bracket on the bottom of their AFM page. I've seen people zip tie them in place. Somebody with free time, a leaf blower, a battery, and a meter must have the urge to compare AFM's. https://www.thezstore.com/page/TZS/PROD/11-3040

I don't think that Nissan changed the calibration of the AFMs over the 280Z years. The engines are essentially identical. And the atlanticz calibration procedure is not year specific so it won't help, unless somebody else messed with it and you want to get back to spec. And, I have a 1978 AFM that has the fuel pump contact switch. It's just not used. The 1978 wiring diagram even shows it but labels it as "useless". Anyway, if it's a new MSA refurb product you probably don't want to mess with it. Just put it on and run it. Mess with it if it has problems.

Didn't know you were doing a restoration. Actually don't even know what year you have. Many ways to get it done. Here are the Rockauto pages showing the difference between 71 and 73. Add some detail and the resto guys will have answers. If the MC is bad, the Master-Vac might be also. Better check that too. It's another hard to find part. https://www.rockauto.com/en/catalog/nissan,1971,240z,2.4l+l6,1209158,brake+&+wheel+hub,master+cylinder,1836 https://www.rockauto.com/en/catalog/nissan,1973,240z,2.4l+l6,1209170,brake+&+wheel+hub,master+cylinder,1836

Probably easier and more effective to buy a reman MC. The kits can be expensive, if you can find the right one, while a reman MC is fairly cheap. The various brake and clutch cylinders go bad easily if they sit unused. Might as well take yours apart before buying a kit, to be sure the cylinder isn't pitted. If it's pitted, it's toast. Here's the 1972 diagram showing how the front and back are "stacked". One pushes the other.

Those are common Bosch injectors for the NA ZX engines. It's not clear if Nissan installed them or they are a common dealer replacement but many ZX's have them. I picked up a set myself from a wrecking yard car. Here's a recent re-energized thread about them. The last post is informative. The picture below shows the Nissan version of what you have. Put some new fuel injector hose on after getting them cleaned and they should work fine, unless they've been exposed to moisture. Apparently the innards rust easily. The hose replacement procedure is in the Engine Fuel chapter of the FSM.

Your symptoms seem to indicate that the brakes don't need bleeding, that you're done. Or that the NP-valve is clogged. With the bleed valve open in the back does any fluid come out of the hose when you press the pedal? Make sure the bleed valve is fully open. Won't hurt to blow a bunch of fresh fluid through the lines. A speed bleeder valve helps a lot to just purge the system. Pump the pedal and keep the reservoir filled.

Post a picture. Stand it on end so that people can imagine it taking up not much space in their garage. Put two starter bolts in so you don't damage the input shaft. Put a bow on it.

Green is the color of Nissan NA units, but it's also a common aftermarket color. They're probably Nissan NA injectors. We still like to look at pictures though.

Post a picture of one. Try to get the part number also. Nissan used a common part number but different colors for their injectors. If they're aftermarket the part number might tell something. If they're Nissan the color will. Cleaning injectors isn't worth a lot but the flow testing will be valuable. Don't do cleaning without flow testing.

I don't try things that don't make sense. The bias would be 75:25. That's not negligible. So, in sum, you've used the Toyota calipers and the car stops, about the same as it did before. Less pedal effort, level undefined. That's about all there is to this discussion. Good luck Jeff.

That joke isn't even funny. I'll simplify my argument - if brakes same why bother.

You used the vague term "perfectly well" again. Nissan has a test for proper brake bias, where you lock up the tires to be sure that they're balanced. So here's the logic - if the stock parts give proper brake bias, how can the Toyota calipers be "better" without changing that bias? And if they don't change the bias how can they be "better". They would be the same. And if they're the same, what's the point of using them? That's the issue that always comes up with these "upgrades". What is being improved? All you're saying is that you did something and the car still stops.

I was being sarcastic about about tzagi1's use of the word "fine". Your brakes were "fine" with the stock caliper. With the four piston caliper and bigger pads you created a front bias. Not fine anymore, weaker in the back now. Now your front pads and rotors are doing the bulk of the work. The purpose of the NP valve is to get all four tires contributing to stopping equally. The whole car is designed to be very well balanced. The stock stuff works really well when it's working right.

Just remove the rear brake system and block the lines. Then you won't have to worry about leaks. It will work "fine".

I was indirectly asking/inferring why you didn't just use the stock calipers. Plus the fact that you didn't complete the job. Have you bled them yet? There is often loads of fun for that with the various brake "upgrades". The NP valve is not adjustable.

What will you be using on the back to match the lower pressure required for the fronts? It's unbalanced now. I tried to browse through but didn't see anything about the master cylinder either. The four pistons use more fluid so you could get extra travel in your pedal if you don't increase MC diameter.

I wonder if some guy was really sneaking around there with a big hand held camera. Must have been way back in the shadows. It was pre-mobile phone.