NewZed

Not sure who Wal is, but here's one - http://www.classiczcars.com/files/category/1-wiring-diagrams/

How about FPR performance? Missing vaccum hose maybe, or connected to wrong source.

There are a couple of bullet connectors in between the CHTS and the computer. Could be dirty or shorted. That's why the numbers are needed.

What numbers did you get? Did you get an open circuit when you disconnected the CHTS? Do the resistance numbers match the chart? Are you testing the right pins, 1983 ECCS? The answer's in the details. "Did it" isn't enough.

Test the CHTS pins at the ECU connector.

You might have a noisy ignition circuit, on your Hz reading. Could be sign of a failing ignition module. Or you used AC instead of DC, or need a better meter. Who knows. People have reported sticky needles causing tach problems. Could be when you had it apart you torqued something. Maybe take it apart again again and twist things around a little until the needle moves more freely. Could even be a piece of goo on the needle stop. Or there's a zero adjustment that needs a turn, or got turned. The other gauges have some adjustment screws on the back, some are usable and some are glued once set. Worth another look. Apparently the voltage tachs work like volt meters, averaging each pulse over time. Maybe you've got a an offsetting ground loop on the tach ground. That's just a WAG. You could jump the terminals while it's out and see if it you can make it work right. The diagram is in the FSM.

Don't give it all away! Gotta leave some fun...Four cycle engine, six cylinders, RPM, and all that.

You'd be measuring coil discharges. Voltage changes that your meter will count. In events per second, aka hertz.

The internet says that new is still available. http://www.carpartsmanual.com/datsun/Z-1969-1978/axle/rear-suspension/2 http://www.nissanpartsdeal.com/parts/nissan-assy-strut~55303-n3425.html

What dimensions are you using now? You said that you have one. The numbers are all over the internet. Check a few sources and you'll probably find a common set of dimensions.

If you have a decent meter that measures Hertz/frequency, you can get a number from your coil terminals and do some math. Or just drop idle speed way down for setting timing. Once you're below 1200 the mechanical advance mechanism should be fully retracted. You could also watch the timing while you drop idle speed, until it stops retarding. Many ways around it. In the long run that "0" is going to bother you though.

The 1978 tach use voltage, not current. Not that it matters probably, because the 35+ year old tachs tend to go bad eventually. Did it work on the car it came from?

The wedge is there to keep the chain from falling down and off of the lower sprocket, and to keep the spring-loaded chain tensioner from coming out of its hole. So, it depends on where the wiggle room is. If the wedge is of the proper dimensions it should be possible to make it tight. Just hit it harder. Some people don't use the wedge they use a tool with a handle of the proper size to do both functions.

Do you still have the original gasket?

There's a thread or two on this forum somewhere with pictures of many different head gaskets. The hole controversy pops up every now and then. You might see if you can find it and and the pictures.

Don't overlook that the Nissan engineers may have designed the head gasket to control flow through the head and block. Would't be surprising to find that they blocked a passage, after the head and block were designed and in production. You'd have tom compare holes and their sizes to a Nissan factory gasket to know for sure. You're assuming that all of the holes need to be open.

You edited and still came up with this? Unintelligible. I was just pointing out that your comment about the HG not fitting your F54 block was irrelevant. But you're right, an F54 and a P90 are a stock 1983 configuration. You should have posted the brand and part numbers of the three HG's you got. There might be a clue there. Besides that, they're all "aftermarket" if you get them from a parts store. The parts store guys only work from a database of car brand and year. You should have told OReilly 1983 280ZX Turbo

It's the holes in the head that matter. The coolant flows from the block to the head and if there's no hole in the head the coolant has nowhere to go anyway. No need to match a hole in the block if there's no hole in the head to receive it. Once it gets in to the head it flows out through the thermostat.

Generally, for a long beam you want to avoid stress risers, areas that will do all of the bending as loads concentrate there. So you'd want them to be the same gauge and size as the frame rails, with smooth welds and few discontinuities (bumps, crinkles, bends, etc.). Nothing is completely rigid so you want the loads and subsequent bending to be distributed smoothly down the length of the beam.

Read John Coffey's recommendations also. The roll cage seems to cover all bases. A frame in a box.

The Z cars are a monococque, or unibody, chassis. Essentially just steel boxes with stiffening elements, either extra "rails" or bends, strategically placed around the box. And the stiffening is done to specific purposes. You're implying that you'll be drag-racing since you're talking about high power. Thicker subframe connectors might be oversimplifying your situation. Generally, people recommend a full cage if you really want to stiffen things up. SunnyZ and RebekahsZ do drag-racing. Read through their past threads.

You are correct.

Search "wrong clutch collar" or "wrong TOB" or "transmission grinds" or "92 mm" and you'll figure it out. Did you match the TOB collar to the pressure plate? That's the most important act when installing a new clutch.

Ponder a complete set of combustion events (two revolutions) and you'll realize that there are always valves open. Look closer and you'll probably see that there are more than just two open.

Another reference source for you is the FSM. The specs. for the master and slave are not called out differently for NA and Turbo even though the disc and pressure plate are. A clue.