NewZed

If you use tiny tires with the 3.54 you can get the same overall ratio as with the 3.9. Edit - actually, they don't have to be tiny. There's not a ton of difference between them. 3.54 - higher top speed, 3.9 - quicker (more acceleration from a stop).

Automatic?

The octane rating specified by Nissan for the stock 8.3 CR L28 in the 280Zs is 91. Are you planning your build for the capability to run low octane gas? If you're doing a stock rebuild, the octane rating specified is probably in the Owners Manual for the year of the engine. For whatever it's worth...

The GR-2 is called Excel-G now - http://www.kyb.com/service/color.php I don't have much shock experience, I've only experienced stock shocks (oil-submerged inserts in the strut tubes), one of which was blown and bound, and the KYB GR-2/Excel-Gs that I replaced them with. The KYBs are much better. I don't really notice them, which seems like a good thing, no urge for something better. It's a street only car. My car is also lowered about an inch and a half on cut springs, with no problems. The ride is firm and they take the bumps well.

Tsk, tsk. All of these facts in the first post and you could have had all of the answers in post #2. You might be able to derive it using the measurement given and the photo. Take the ratio. You'll have to estimate the camera viewing angle. You can even see where the seal rode.

With the regulator unplugged, the power to the windings in the alternator is gone. No power means no magnet means no charging. If you got 17 when it was plugged in that means the alternator works. You most likely have a break in the wire that tells the regulator what the voltage of the system is at any point in time (the current voltage, no pun intended). In an internally regulated alternator it would be the S wire. I don't know which wire it is in the external system. The FSM has a good description of how the external regulator works and, I believe, describes which of the wires to the regulator is the one that should be connected to battery voltage. It also has a test procedure for determining if the regulator is working correctly. It porbably has the typical bad/good test and a more involved test and adjustment procedure. You should go through the tests in the FSM and report the results back to the group so there will be something concrete to work with. You will probably find one wire that is dead when it should have battery voltage.

Here's what they look like - http://www.thezstore.com/page/TZS/PROD/14037N36 Don't know why MSA calls them "spacers", maybe because they span the space between the manifolds. Even the pros are confused.

I haven't seen this noted before but wouldn't the 60 - 90 psi of a stock EFI unregulated pump crush the floats in the Holley? Just a thought, there may be more work to do if he's got the EFI pump on. Just noticed that the OP has been driving this around like this, with the intake half-bolted on and the Holley pouring fuel in to the manifold leaking on to the hot headers, revving to high RPM. It's got to catch fire eventually.

Follow the flow path of the gasoline from the filter through the lines to where ever it ends. It doesn't flow through the intake manifold. You're missing the clamping washers. Each stud or bolt holds between the intake and exhaust splits its clamping force between them. It's probably not idling because you have a huge intake manifold vacuum leak. You have quite a bit of work to do to get things right. If you've been trying to run it with the gas leak and the vacuum leak, you're on the edge of an engine fire. Lean backfires and gas fumes are a bad blend. The pictures are better, at least they are equally gigantic. Good luck.

You covered all of the basics in your first post. Probably why you got no replies. Spark present, fuel present, timing checked. Doesn't make sense that you don't even get a pop, unless you have zero compression...

The intake manifold isn't leaking gas, the carburetor or the fuel lines to it are. JSM's circles are in the right spots. There is a thick washer-shaped curved piece that goes over those studs to span the gap to the intake manifold and clamp it on the edges. The studs apply clamping force to both the intake manifold and exhaust manifold (header flange in your case). There's no reason for your clutch linkage to increase engine speed unless the pedal is rubbing on the throttle linkage. The PO might have run a cable linkage to your carburetor and the clutch pedal is pressing on it. Also, check the carpet down by your feet.

#24 here has some numbers - http://forums.hybridz.org/index.php/topic/57510-powerforce-harmonic-damper-install/page__st__20 I searched "damper pulley fit" just to see what was out there. Worth a look. Edit - Post #34 is even better, with an actual measurement. Of course, after reading the thread, you'll realize that yours will not be exactly the same.

I think that he might be worried about fuel pressure control response time over the length of the small diameter tubing. I've pondered it myself. If the pressure didn't build quickly enough at the injectors because the extra line between the injectors and the FPR took time to pressurize, then you could imagine a lean condition when lifting throttle or shifting down a gear (higher intake vacuum at the FPR). How lean and whether it's significant, who knows.

It might not be durable enough for the heating cooling cycles of the exhaust manifold, at the flange, but who knows. Here's one example - http://www.autozone.com/autozone/accessories/VersaChem-3-oz-Inferno-metal-repair/_/N-25hw?itemIdentifier=30671&_requestid=765970 Since you're trying to save an existing system, and can't get reasonably priced replacement parts, maybe a custom copper washer would be in order. Cut a couple of rings from soft sheet to size to fit around the pipes in to the manifold, and let them deform in to the defects.

They're not the same harness. Do a little Googling and searching and read the comparisons between the two and you'll find that the MSA/Dave harness is essentially plug-in and go, while the BD harness is apparently somewhat difficult to get installed. Always a good idea to do some research before making a WAG and criticizing just because something appears to be expensive.

I had a similar problem with my first 280Z exhaust flange. I cut the metal rings out of one gasket and doubled up with a complete new gasket. I wrapped them both in crinkled up aluminum foil to hold the rings in place and to add some filler for the gap. The reason I cut the metal rings out was to concentrate pressure in the area that needed sealing (which probably put more bending on the flange, but it wasn't working anyway). My flange and mating surface both looked flat but I couldn't get the leak to stop, like your situation, until I took these "hack" like measures. It was a small leak before but you could still hear it with the hood open and see the carbon trail it left. The hack job did well and lasted ~10,000 miles until I got another down pipe. On disassembly, there were signs that it was starting to breakthrough, but you couldn't tell from outside. Edit - that ceramic muffler sealer you can get at the auto parts store might help also. It's designed for high heat. Any reason you can't unbolt at the anti-resonator and replace just the down pipe or is yours gone?

When you mate the flange to the manifold and tighten the three nuts, do the two surfaces come together parallel and flat? On the Zs, typically, everything hangs below the mounts so you can tighten up the flange before flexing the pipe whatever small amount is necessary to get it on to the hangers. There's enough wiggle room to make sure the gasket is seated and everything comes together right. The first hanger is back on the tail shaft of the transmission, which moves with the engine as a unit anyway. The only attachment to the body is the rubber hanger way back at the rear bumper. It sounds like your system is too bound up to get the flange and manifold mating surface parallel and tight.

The FAQ page on megamanual.com answers many of your questions. On a PC you could use the Find button and search for "sequential". On a Mac I assume that you just think about it and it appears in front of you. Kidding. Sequential's benefit is mostly in a smoother idle and cleaner emissions. http://www.megamanual.com/MSFAQ.htm

Is it supposed to have a radical cam installed? Lumpy idle with a mild cam is not good. "Smoke" in the intake is worrisome. Overheating isn't good. Is there another digit after the "1 hg"? One inch of intake vacuum is not much. Good luck with it. The guys that build up the small block chevys might have some comments. I haven't had one for many years.

There's not enough information in your first post to really say anything. Did the engine get to full temperature, was it smoking while you were setting the timing, was it oil on the plugs or oil and gas, were the plugs new or old, was there so much oil that the plug fouled, did you drive the car, etc. A little wetness on the plugs of a cold engine wouldn't be super unusual. Start it up and monitor vital signs like oil pressure and temperature. Get it up to normal operating temperature. Listen for unusual noises. Look for smoky, smelly exhaust. Drive it if possible and see how it runs.

How long did it sit before you started it?

Sorry about that, my mistake. I must have figured it out from the FSMs. But I don't think that you need a later EFI car ignition relay for what you're doing. It probably has more functions than you need. You just need to power up the EFI harness through the fusible link circuit. A single relay could be used there, activated by splicing in to any switched power wire. That will power the injectors. Then jump power to the ECU through the connector or use another relay. Another relay for the fuel pump. The typical BMW Bosch style relays are simple and durable. It might be easier to think of the engine and EFI system (ECU, injectors and harness) as completely separate from the car and supply it what it needs to work. Use the car's harness only to supply power, either directly, or to activate individual relays. I'm probably over-simplifying, and may have left something out, but I did get an engine to run with just the EFI harness, an ECU, an old defroster switch (to control power to the ECU) and some jumper wires at one of the connectors. The ECU needs that inline resistor as a branch on the Pin 1/tacometer circuit also, to work correctly. I used a separate GM HEI module for ignition control with a stock 280Z distributor. Good luck.

Look up your part here - http://www.oreillyauto.com/site/c/home.oap - then click the Compatibility link in the part description. It will tell you which other models and years used the same part. Pretty sure yours is the same up to at least the 79 ZX, maybe farther, and back to 76, maybe farther. My 76 was hot-wired straight from the ignition switch to the relay when I got the car, because the insides had rusted away. I replaced it with a 79 ZX relay. The later relays had a separate ground pin, but the function of the connector pins is the same.

The pictures are way too big. The ones in the second post never even loaded on my system. Most photo editors have a "save smaller" or import to a certain size function.

I'm not beerman, and have only taken one transmission apart, partially, but it looks like three of the gears on the countershaft in a 4 speed are either cut as part of the shaft or permanently bonded to the shaft. All of the main shaft gears will come off, but only reverse, and the main drive gear can be removed from the countershaft in a 4 speed. Actually, in the 1978 FSM, Nissan doesn't even call out a counter shaft anymore, just counter gears and parts. It looks like they made some signifcant modifications. There is no distinct shaft just a stack of gears and a splined mini-shaft that all get stacked to work like a full length shaft. The synchro pieces are all on the mainshaft though, so if you had a 4 speed with good synchros, those might be some parts worth swapping, as a gear and blocking ring assembly. Although the different wear patterns might cause some noise. As far as ratios, the 71C transmission has the lower 1st gear and an even spread between gears. 1st, 3rd and 4th are like the early 5 speed, but 2nd has been moved to even out that 2-3 gap. One more option, but requires some work.