NewZed

That's a nice looking setup, with the custom supply and return lines. Are you making those or piecing your own package together? Designed for the stock Nissan two port FPR's?

The 280Z's were designed for half-shafts with R200's. It would be odd if they were binding and even if they did I think it just pushes the strut outward, and/or causes the suspension to bind. What brand of u-joint did you break? Just for the record. Might be cheaper/easier to find half-shafts like RZ suggested, that have the precision-fitted factory u-joints. Nissan put a lot of effort in to making the u-joint fit perfectly.

That's different than a 280Z's. But that's what "vacuum relief valve" means on the diagram I attached. If you have a mighty vac you could probably rig something up to see if the valve opens. Or if no one is looking you could suck on it, procedure described in the attached picture. By the way, all of these pictures come from the final few pages of the 1983 EFEC chapter.

If it's not just your imagination, it seems like tank venting might be involved. Not through the cap but through the charcoal canister and its vacuum lines and vent hoses. It may be that it's not lack of fuel but overpressure. Just a guess. Maybe you're boosting the fuel tank. The cap should have a little spring-loaded valve on the inside center. Take a look. You can pick it open with your fingernail. It lets air in but none out.

Don't forget that the fuse is just a thermal overload device. Heat from other sources can push them over the edge. Maybe your relay board is in a hot spot. The pump motor failing from overheating is not the same as the fuse blowing from excess current and overheating. If the fuse was sitting next to the pump where heat could be conducted through the wire to the fuse that would make some sense but the relay board is probably 12 feet away from the pump. It doesn't see any pump heat. You said that you have the stock tank with stock return lines but the only car in your sig with MS is a 73, which has the small return lines. Probably not the specific issue though, since if you had back pressure at the return line your fuel pressure would be uncontrollably high. Edit - the older 240Z fuses were known to blow and/or melt their surroundings due to poor contact at the fuse, allowing corrosion and a high resistance connection. It's resistance at the fuse area that produces the heat that blows the fuse. Increased resistance at the pump lowers overall current draw and saves the fuse. If pump motor resistance drops when it gets hot that could cause excess current through the fuse. Focusing on heat is right, but the general "heat is bad anywhere" view isn't going to get you there.

I'm not sure this logic works. There's a lot of fuel available for cooling, if it's flowing. Why don't you get rid of the pre-filters for a while and see what happens. Or at least confirm that the flow rate of the filter matches the flow rate of the pump. 100 micron particles probably require a pretty large surface area to allow a high flow rate. "100 microns" doesn't tell enough. Also not clear on how a hot pump draws more current, causing the fuse to blow. A non- or slow-spinning DC motor draws more current, I believe from my limited electrical knowledge. But a hot motor, maybe not so much.

Pin 1 at the ECU connector needs to be connected to coil negative, and the tachometer and its resistor need to be in place. The tachometer is also connected to coil negative and has an effect on the Pin 1 signal to the ECU. I don't know exactly what range the ECU works in so a meter reading probably wouldn't tell very much.

Fairly common. Shouldn't be very hard if you have the EFI harness from the 280Z or ZX. Details returned proportional to details given.

Probably a Pin 1 problem. The ECU needs to know what's going on.

"VG30E" isn't really very specific. For instance, Nissan went to sequential injection in 1990 for the 300ZX, which would be a nice upgrade over batch or semi-batch. I would think a 1990 to 1995 VG30E system might be the way to go. Somewhere in the 90's I think the systems got extra complicated, maybe 96. But pre-1990 might not be the way to go when there are tons of the early 90's VG30E cars out there. Pathfinders and Maximas, for example. cgsheen has done the swaps though so would know better.

Any or all of the three here could have a 3.9. Might be within distance for you. http://row52.com/Search/?Year=&LocationId=0&ZipCode=97225&Distance=250&MakeId=&ModelId=1572&Page=1

https://www.diyautotune.com/softwarelinks.htm

The cams have letters on the back, and the heads have numbers and letters at the bottom front of the head. No need to look for square ports.

Four year old fuel?

This is why you need to just start bolting things together. Then you'd know that the water pump doesn't use the AC idler.

Hydro-locking bends connecting rods. Have you had the engine apart yet? You might need more than pistons. How can you collect parts if you don't know what you need? Curious on how that much water got in there. Did you not have an air filter?

Automatics use a different bar. You can get a new one for $314 from Courtesy. http://www.carpartsmanual.com/datsuns30/DatsunZIndex/Axle/RearSuspension/tabid/1731/Default.aspx

I would read jmortensen's diff thread in the FAQ section. You might have some changes from stock. A welded R200 might be going backward. Or maybe Nissan converted to clip-in axles with the 280Z R180's. Edit - actually that picture I posted is from the 77 FSM. So what you have doesn't match. http://forums.hybridz.org/topic/49194-differential-cv-lsd-hp-torque-r160-r180-r200-r230-diff-mount/

Maybe somebody buggered up the studs and replaced them with bolts. Posting a picture re the axles.

Without exceeding the speed limit, of course.... Drive at your own risk.

The trip meter shows that the cable is turning. The older speedometers use a rotating magnet, and a cup or disc shaped thing, and a spring to show speed. There's pictures out there is you search "how a speedometer works". You probably have a spider web or some sort of crud in the mechanism, its kind of sensitive. You could try to spin it free by driving really fast or use a drill motor on the cable end, or take it out out and see if you can break things loose by shaking it. Or take it apart and see if it's cleanable. There's a nice picture in this link - http://www.uniquecarsandparts.com.au/how_it_works_speedo.htm

Firstly, you should probably start your own thread, describing what you're trying to do. Talking about getting an old engine running at the tail end of a thread about shaved intake manifolds won't draw much attention. Second, that's not a stock combination of parts. But you should be able to get it running well with the stock ECU, others have done it. But it's a low compression ratio engine. It's already at the typical turbo engine compression ratio. But you should know that already, it gets talked about all the time. Not many people, if any, run electric water pumps. With that pile of parts and planning for electric water pumps, you have a lot of work ahead. Probably best to just get some new gaskets and start bolting the parts together. Get the engine in the car and get it running. You can bolt any turbo parts on with it installed, and convert to Megasquirt too. Getting it running in "stock" form will let you know if the engine is even worth keeping, and you can learn as you go, and drive the car.

Coolant flows from the block to the head. The gasket would be designed to control and balance flow in to the head, I would think. So if all of the holes in to the head are open, you're good, the gasket can do its job. Seems like the gasket that matches the head would be the way to go. If there are holes in to the head that don't have a matching hole from the block then that's where working on the block to give the head what it needs might matter. I haven't seen where anyone's done that but maybe it happens.

The eight holes are two different four hole bolt patterns. Designed to fit two cars. Pretty sure the pattern changed somewhere on the way from 240Z to 280Z.

It always helps to describe what you do know, no matter how little. Just to show that you're a good investment. Or at least post some pictures for entertainment value. If you can't figure out the cold start injector, Megasquirt will take forever.