NewZed

Also, if you "tighten up" the AFM you're actually reducing fuel. Implying the opposite of a vacuum leak. Maybe a blown FPR diaphragm?

Not so sure that your symptoms point to a vacuum leak. How about fuel supply? Did you measure fuel pressure?

I meant to edit out the part about the gears. When I was trying to get rid of the clunk/thump I found that the more I tightened up the diff mounts the more gear noise I got in the cabin. If you got a stock R200 from eBay then any gear weirdness probably stayed with the old diff. You can't just eyeball the diff mounts. Former owners do weird things and the parts are over 40 years old. You really need to get up close and make sure they're correct. The rubber in the front mount collapses and the metal from the top piece can rest on the crossmember. Metal to metal contact.

Sounds like the gears aren't meshing well. If you don't get the differential isolated from the body you'll hear the gear howl. I'd focus on the mounts. The front mount and the mustache bar bushings. What do you know about them? Do the urethane mounts have the proper metal sleeve inside? Are they compressed against the body? Does the diff have a solid front mount, or a collapsed front mount? You want the path from the diff to the body to be interrupted by rubber or urethane.

Try to find a wiring diagram of a BMW that uses the switch/sensor. Maybe the BMW boards.

I went with those pads on my 76 and replaced them with Beck Arnley after just a short while. They didn't have any initial bite when you first pressed the pedal. Took extra effort to start the stopping process after you felt the pads hit the rotors. The Beck Arnley pads had great pedal feel, very noticeable. But they wore faster and dirtied up the rims. I never tried to lock them up and had 205's on so might not apply to what you're trying to do. If you still have drums on the back you might pull them and check the actual contact patch. Mine only contacted at the ends of the shoes. I could not lock up the back wheels with the parking brake. Very little stopping power back there. The lack of quality shoe options is actually a valid reason to swap to disks on the back.

Metallic or organic? That's a wide tire. https://www.rockauto.com/en/catalog/nissan,1976,280z,2.8l+l6,1209226,brake+&+wheel+hub,brake+pad,1684 https://www.rockauto.com/en/moreinfo.php?pk=298558&cc=1209226&pt=1684&jsn=898 https://tiresize.com/tiresizes/225-50R16.htm

Might be the backing plate rubbing on the drum. Happens if you set the strut down wrong or accidentally hit the plate with a hammer. You'll see rub marks if that's the case.

The suggestions about the pump are good. But your symptoms sound a lot like pressure is bleeding off overnight. Do you have a factory FPR or aftermarket? The typical aftermarket regulators all bleed down quickly. You can check all of the possibilities by attaching a fuel pressure gauge and watching it.

You could have torqued the bolt to 100 ft-lbs by now. Easier than all of the words, probably, and will tell you more. Good luck. p.s. cutting a groove like that is almost exactly what you would do if you were trying to remove a stuck bolt in a tube and heat didn't work. The metal stretches at the groove and the bolt is freed. Same concept as cutting along the length of fuel hose stuck on a barb. It releases before you get all the way through.

Your plugs are either oil-fouled or fuel-fouled. But they are not lean-fouled. Make it leaner. If it doesn't run right because you're too lean then maybe you have a ring-sealing problem. I'm sensing subconscious "I just rebuilt the engine it can't be the rings" thinking. Just a suggestion. And, like others said, get some known plugs in there. Those multi-electrode plugs are gimmicks. The basic concept ignores the fact the fuel-air mixture is moving rapidly past the spark point. It's not a static situation. All that extra metal cools the electrodes also. The electrode (ground strap) needs to get hot and stay hot so the carbon burns off. Gimmick.

The tube is a fine thread precise fit. It's a dilemma. Welding one side will probably warp it enough that the bolt might not fit anymore. Put some thought in to a plan.

The metal tube does not rotate around the end of the arm. The rubber flexes instead. That's why you're supposed to tighten the bolts with the weight of the car on the suspension. A picture of the end would be better. Thread the bolt in and see if you think there's enough metal left to hold the torque. 100 ft-lbs. That's the real concern. If the tube splits and the bolt loosens the control arm will get loose.

White smoke does not come from "lean". You're starting from a bad assumption.

Not normal. What size tires? What type of pad? I think that ceramics have a lower coefficient of friction. https://ctbrakes.com/brakeanswers/friction-compounds/ On the back I found that typical parts stores shoes are meant to fit a larger diameter drum. Only the ends contacted the drum when used. But the back tires still locked up when I was having front brakes bleeding problems.

More fuel or less fuel? "fingering' doesn't really tell much. I don't think the engine will run on one cylinder. So, it's still not clear what you mean. Don't overlook the simple "fouled plugs". When the cylinders don't fire the plugs tend to get dirty. Plug examination usually tells a story. And - bad fuel.

If it was running great before the first thing you should do is to put the AFM back exactly as it was before. "Adjusting" AFM's ruins most of them. Nissan puts glue on the wheel because they're only meant to be adjusted when calibrated then never touched again. One cylinder must be an exaggeration, right? Post a video. Are you sure that you didn't bump something or do something that you think "should" have no affect? Because there's nothing you've described that is a clue. "Engine ran great, worked on engine, engine runs terrible" is all that's here.

Vapor, gases, "air" that was dissolved in the gasoline (it's a thing) but degassed when the pressure was released...I should have been specific. But, as someone who had an Aeromotive FPR for a while I know the sound of "non-liquid" being pushed through the rail and back to the tank when priming the system. The rail empties of liquid and fills with non-liquid, vaporous substance. The injectors are very hot after an engine runs and just percoate the liquid out until they are dry (I assume). Then the new fuel has to come back in and refill each injector and pressurize it so that it will squirt the proper amount of liquid out when the injector opens. Or, in short: no leakdown = quick no-prime start; leakdown = prime ,wait, start after extra cranks, and maybe some rough revolutions before things smooth out. It's really just where a person wants to be on the daily driver/race car spectrum. I got tired of priming and waiting so modified a Bosch regulator, for convenience.

The issue with the pressure bleeding off is that restarting the engine after a day or two is difficult. The fuel rail typically empties due to the heat from the engine. Even if you prime it it's still full of air bubbles. Besides that, if you're going to prime then you have to add another switch to run the pump. It kind of boils down to how involved a person wants to be in getting their engine started. An FPR that doesn't leak down will start faster than one that does.

Does it hold pressure when the pump is not running?

There is a vacuum port on the FPR that increases or decreases fuel pressure based on intake manifold pressure. The factory Nissan turbo system uses a simple FPR with a reference vacuum/pressure line. It maintains a constant pressure so that the ECU can adjust injector flow rates accordingly. Here's a description. https://www.haltech.com/why-you-need-a-fuel-pressure-regulator/

If you're using 440cc injectors you must have aftermarket engine management. So you don't need an adjustable regulator. I'm a big fan of factory designed parts, they're made to do things like hold pressure and last 100,000 miles. I'd just find a 2.5 or 3 bar factory FPR and plumb it in. Actually I'd go with the higher pressure to combat heat soak problems that the Z's tend to have. Example below. I don't know if that's 3 bar or not but the form seems right for what you're doing. https://www.rockauto.com/en/catalog/bmw,1985,325e,2.7l+l6,1011643,fuel+&+air,fuel+injection+pressure+regulator,6124

Here's an interesting thread. It's funny how people who don't have the problem think they understand it better than people who do have the problem. People are strange. https://ls1tech.com/forums/fueling-injection/1830922-want-aftermarket-efi-regulator-holds-pressure-key-off.html

That's a salesman who found out that it doesn't hold pressure so answered a question that you didn't ask instead. "Fluid in the lines"? C'mon. "Tech staff" is probably one guy, maybe even the same guy you were talking to, switching hats. All of those aftermarket companies use the same design, a ball-shaped valve in a large round seat. They just don't seal well. I tried to find a price for those Bosch parts on the internet and they seem spendy. And I only found a place in Australia that sells them. But a call to the local Mini dealer might get better results. Good luck.

I had an old style Bosch adjustable regulator with hose barbs that I modified to have a vacuum reference. Here is Bosch's modern version that already has a vacuum reference port. Mine did not leak down. It acted like a normal modern car FPR which does not leak down. Edit - I'm not really sure how it's plumbed in to their system. The flow happens between the O-rings. But it might give you some ideas. https://www.bosch-motorsport.com/content/downloads/Raceparts/en-GB/50154251144125323.html#/Tabs=50170635/ Edit further - actually they have an adapter. If I had the money and was building a system from scratch I'd probably go with the Mini A and the adapter. A person might think that priming the rail before every start is no big deal but being able to jump in and turn the key is much better. https://www.bosch-motorsport.com/content/downloads/Raceparts/en-GB/50225163113309707.html https://www.bosch-motorsport.com/content/downloads/Raceparts/en-GB/109952523.html