Zed Head

That seems to be the assumption that is made, based on appearance. But there is no data to back it up. The big rectangular exit hole of the N42 head looks better compared to the N47 hole. Bigger is assumed better. But...no proof. And Nissan's specs are exactly the same. Just adding some info for wil849's search. Lots of ways to spend money with no significant benefit. And possibly make power costing mistakes, like putting round headers on square exhaust ports.

That's bad research. They are identical except for the exhaust port liners.

Don't forget that the switch is normally closed. It opens with oil pressure. That's the flaw in it, if you unplug the oil pressure switch the fuel pump runs with the key On. You'll need another relay to make it act as a safety switch. That diagram hurts my head...

You're going to swap a similar head on to an existing short-block, and install a high-performance cam shaft. So far. You could just install the cam shaft and save the head swap money.

Of course.

Two prongs is correct. One prong is the pressure sensor and the other is the switch. Maybe you picked the wrong prong? Bottom of the T is the switch.

The engine has a head on it. Looks like either an N47 or a P79. Are you sure that's not a 280ZX engine? If it's an N47 head there's no real benefit to swapping to an N42 head. It's been very well described all over the Z sites about where the ID numbers are for the engines and heads. Get those numbers and you'll be way ahead.

Better top off the battery. It's low.

I don't think you mentioned the whine before. Might be that the whine and the vibration and the 4th gear synchro problem are related. Maybe a bad bearing.

Factory 280Z engines had 8.3 CR.

Not enough info. Many piston-combustion chamber combinations.

Redline MT90 has a dramatic effect on worn Nissan synchros. It's not hype, it really works. I had a 3rd gear grind on a 78 5 speed and Redline made it go away, over Valvoline 80W-90 gear oil. It's a cheap fix attempt. Pennzoil Synchromesh has a good reputation also.

Just realized that yours has lost its bottom plate. The countersink is actually a bigger hole in the the bottom plate (missing in your picture). So it's broken and won't work anymore. Better get a new one. http://www.carpartsmanual.com/datsun/Z-1969-1978/axle/rear-suspension/83 https://www.courtesyparts.com/?p=catalog&mode=search&search_in=all&search_str=55418-N3701

They did countersink the mounting holes though. It's a very strange part.

Don't you have even one for this thread? p.s. I wouldn't put my email address in a post. That's just asking for spam. Use the message function.

You have to read through that whole thread to realize that there was confusion about a retrofit, and a factory installed part. The factory part is just steel. Yes, they all look that bad. I've seen many in the wrecking yards, and I have three. Even Nissan tried to hide them, and only showed an edge.

If it's a brand new engine it might still be tight. So right before rotation stops the parts grab and give everything a little shake. It might get better with time. Just a guess.

It's fine as long as you don't crumble it up and create dust. Like the lead in paint.

It probably had it at one time. What's surprising is that Nissan didn't at least polish them up after their introduction. 1978 is just as ugly as my 1976. They make a good portable shop anvil. Your link didn't come through. Here it is...

You might be able to flare the end with the proper flaring tool. I think it's called a bubble flare. If it's the return line it's under low pressure so not a big deal. Try to blow back through both. The return line won't have a restriction. That could also be the vent line, which has a check valve in it. The end of the vent line goes to the charcoal canister. You could also get a compression fitting, or put a 45 degree flare on that tube end and add the proper bubble flared stub piece of tube. Many ways to avoid a major replacement job and still be safe.

Good point. Nissan confirms...

Holy moly. Is this a resto or a resto-mod? It looked done to me when it was sitting on the trailer.

Describe the stalling. That's the best clue.

From one of the other threads - "Stalling under load. First thing we chsnged the fuel ilter. Put low octain gas in it. Had it checked out, fuel and air pressure ok. Has new plugs an wires. Any suggestions ? We thinking fuel injection sincere issues? Any imput or knowledge of same problem is greatly appreciated. Tks"

Stop starting new threads. Stick with the first one you started.