Zed Head

Thanks. The other part of the question is how does the guy with the channel benefit? Why are they asking people to subscribe? You can see the number of views on the page.

Wow. I wonder if there's burnt oil on the inside of the valve cover. Must have got hot. That kit looks about like the top bracket I had on mine. Any chance that there's another hole in the firewall for the slotted tang to fit over? That would determine your upper limit. Maybe the tray is thicker than stock. I'm going to guess that that's the issue. The tray is probably sourced from a non-Nissan supplier. Find a thinner tray. Actually, if the bracket fits the correct hole in the firewall then your only major adjustment is the tray. The top position is fine-tuning within the length of the slot. If the battery sits on the tray and you can close the hood without interference, then the firewall hole seems like the fix. You might check the tray first, because the top bracket looks right.

Just curious. I've been watching a few different youtube channels and the producers of the channel often ask viewers to click the subscribe button. But I don't understand what happens when a person "subscribes". So, what happens? Why is it important?

I think we need a picture or two, at least the first one for sure, and maybe some details on where you bought this "kit". I've not really seen your problem before so maybe there's simple solution. But I really want to see a battery welded to a valve cover. Please.

Replace it.

You need more ohms. You could put another potentiometer of the same type in series. Or find one that has higher resistance at the top end. Or add a resistor to the circuit and use the potentiometer for tuning. Old radios use them for volume control. If you have any laying around you could scavenge. At least you have a path to explore. Might at least show the potential of something like Megasquirt.

Keep turning the knob until it takes off like it should. You should be able to make things so rich that the engine won't run, you can flood it. Then go back and do something else to try to get the idle leaned out. That's the game, tuning the untuneable EFI system. With the aftermarket systems you change things by computer. You'll need to do mechanical and electrical things directly.

The 280Z's have another knob right next to it for the trip-meter. Turning it won't dim the lights.

George's dad died...

Take a picture. Did you turn the knob?

If you didn't bend anything you could always go back to stock bushings. They seem to be available. If you mean the casting when you say "assembly". You''ll be back to where you started but with new rubber. http://www.carpartsmanual.com/datsun/Z-1969-1978/axle/rear-suspension/57 https://www.nissanpartsdeal.com/parts/nissan-bushing-link~55541-e4100.html

If you have a spare distributor and an ignition module (unless it's a points distributor), and a coil and a terminal wire and a battery, you could make your own tester. Spin the distributor, make sparks, watch the tach. Wish I had parts, it would be fun.

What do you mean by "redo"? I like to use carpartsmanual to see if part numbers changed. Looks like the control arms, AKA transverse links, changed in august 1973. Not clear what the change was though. The axles changed in the cast hubs, somewhere in 73 for the 74 model year, but it looks there were a bunch more changes along the way. Part #1 and 2. http://www.carpartsmanual.com/datsun/Z-1969-1978/axle/rear-suspension

I wasn't joking here. 2200 ohms is a lot of resistance. If the tachometer circuit already has resistance there's no reason to add it in-line. Unless it's for flyback(?) blocking, from the coil discharge. I'm going to guess that without the resistance in the circuit either the tach won't work or the ignition system. Could you measure the resistance through the connection at the tach to ground? That might offer a clue. It's probably in the schematic but in the meantime. I'm not an electrical engineer, I'm just trying to figure things out.

My comment was just from the basics of Venturi and Bernoulli. Where did your pasted picture come from? Actually, there's a balance between air velocity and pressure and needle position (effective orifice size). That's where things get messy. As I understand things the oil controls the rate of piston movement, the speed, but not the steady state. In other words a thick oil and a thin oil should put the piston in the same place at steady RPM. I'm no carb expert but a set of stock carbs might be a good starting point just to see how the combination of engine parts work. Then go to the "upgraded" carbs. You don't really know what has been done to the ones you have.

Round port should work fine on a P79 head. The P79 and the N47 both have exhaust liners that are smaller than the hole in the head casting. It's the liner opening that needs to match and it's round. The liners are designed to get really hot and burn off carbon and, maybe, excess fuel and oil. Keeps the exhaust system, and the exhaust cleaner. The first picture in this link shows the port. You can see the liner in it. http://xenonzcar.com/s130/Heads.html

One possibility is that the pistons aren't rising when the throttle is opened. This keeps the needles low, reduces fuel input to the air passing by, and makes things lean. The pistons' rate of rise is controlled by the damper oil. So, it seems like you have sticky pistons. What kind of oil are you using?

I would start from scratch with this. What are any and all possible causes for an engine to lose power when the throttle is opened?

You're right, I grabbed the wrong drawing. Screwed that one completely. Redo...

Found some good reading. Sure to help a person move up in their career, after things get back to "normal". https://thecooperreview.com/10-tricks-appear-smart-meetings/

Break out that meter and rerun some tests. Sounds like you lost power somewhere, or ground, or the Pin 1 signal. Can't swap until you know what to swap.

Ooops.

It's a lump in the tape of the harness. It's shaped just like the picture. It's in the vicinity of the ignition module. If too much current flows through the tachometer the coil might not discharge. Make then break. No break, no spark. Maybe why it's 2200 ohms.

I'm not sure how idle mixture is set. Usually there's a separate circuit for that. That's the carb tuning game, balancing the various fuel circuits. But at 1/4 throttle you're probably "on the needle", so raising the needle will let more fuel get pulled though the main jet. I'm just winging it from past carb memory. But I know that there's a lot of back and forth and trial and error involved. Good luck.