Zed Head

Sometimes you can find these numbers on the internet. http://www.carpartsmanual.com/datsun/Z-1969-1978/electrical/electric-unit-switch/section-2/240z-260z-(from-aug-73) http://www.carpartsmanual.com/datsun/Z-1969-1978/electrical/electric-unit-switch/section-1/240z-260z

You could also unplug them, one by one, and see what stops working.

Unplug them and see if the shape of the plug and the wire colors match the drawings.

Did you take apart the horn relay? You never showed what was inside.

If the files are on Google Drive you'll need to change the access from private to public. Google Drive is surprisingly hard to use, not very clear. Right click on the image, click "Share", then change the setting under "Get link" to "anyone with the link" by clicking the tiny black triangle on the right. Very convoluted. If you're on a Windows computer you can copy the image to the Clipboard and just paste it directly in to a post. Or, you can save the image as a file on your computer and "choose file".

Not if it's just crapping out then coming back to life. And yes, the big box. They fail in different ways, but dying then coming back to life is one of them. Old "new concept" electronics. 1975 was the first EFI 280Z.

Your links don't work. What else can you say about the engine? Pistons and head combination, for example. I wonder if a low compression engine runs better with more advance. Seems like it might since the pressure isn't there to drive the combustion. Maybe you have dished pistons with a P79 head.

I had a 1978 ECU that did that when I was testing it. Died and restarted a couple more times then I had to jog home and get the original to put back in. Ignition modules do that too. Carry spares.

I would go through the usual confirming that all of the timing marks are correct. Is piston #1 really at TDC when the other marks are zero'ed, or are you assuming that zero on the damper pulley is correct? If you're at 25 degrees and you add in the typical 18 for full centrifugal advance you'd be at 43 degrees advance under acceleration. You should be getting detonation and knocking. Something's off. Does timing advance when you rev the engine and the light is on it?

When you say "run" do you mean idling, or cruising, or getting on it? And, define "crap". Carbs, EFI, engine details will help also. Not much to go on. If cam timing is on the money then stretched chain is not likely. The chain determines cam timing.

Here's another good one for graphical data. https://ourworldindata.org/covid-cases

Google still seems to be the clearest and most up-to-date though. Remember when Google was just a simple search engine? https://www.google.com/search?q=covid-19

The World Health Organization gives the global view. Their web site has a lot of new tools for exploring. https://covid19.who.int/

The CDC seems to be back on track, for the most part. https://www.cdc.gov/coronavirus/2019-ncov/index.html

I think that you can reach it pretty easily. Use your test light and see if any of the pins in the plug have power, with the key on and the fan switch on.

It's like when people run out on the beach after the first wave of a tsunami. We're probably going to have another one. The trend has already changed direction but the money needs to be made. Here we go. https://komonews.com/sports/sounders/sounders-fc-drops-covid-19-restrictions-allows-full-capacity "More than 27,000 people attended the game against Houston Dynamo. Masks were not required for vaccinated adults and no one was asked to show proof that they had their shots." https://covidactnow.org/share/39204/?redirectTo=%2Fexplore%2F39204

You confirmed that there is no power at the plug to the blower?

22/418= 5.3% Is that a lot? How much do the connecting rods differ?

Good point. It would just be a quick blast though, right, then it would fall off? That's the whole thing with current control. I wired my HEI module up in the engine bay and used appropriate wires. Something to consider for people retrofitting a module in the old ignition module cases, as EuroDat's instructions show. That's a long run for small wires. Not picking on the XR3000 but I think that it is basically a small module in a big box. I'll bet if you took it apart there would be just a small circuit board inside. The other possible failure point would be the trigger mechanism, which is the other sophisticated piece of technology.

He's back. They call him BoJo.

Plus more variants. The odds of a vaccine-proof variant increase as more people get the virus. There has already been a UK variant. And people from the UK are known travelers. It's what they do, they travel around the world, regularly. https://www.cdc.gov/coronavirus/2019-ncov/science/science-briefs/scientific-brief-emerging-variants.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fcoronavirus%2F2019-ncov%2Fmore%2Fscience-and-research%2Fscientific-brief-emerging-variants.html And it looks like there's a new one - https://www.sciencefocus.com/news/lambda-variant/

I view it more as long-COVID versus cases. Creating a huge number of debilitated people. That are more easily ignored of course, because they don't have any energy. In a broader view, the question is one of a healthy society versus a sick one. Some people think that more sick people means more for them. Others realize that more healthy people means more for everybody. That's kind of life in America in a nutshell, I think.