NewZed

There's a switch in the AFM and a relay that would be used to get back to factory set-up. See the wiring diagrams and descriptions in the Engine Fuel, and Body Electrical, chapters - http://www.nicoclub.com/FSM/ Since you're asking about a "pressure switch" to control fuel pressure I'll say that you should read all of the Engine Fuel chapter, before you do any work on the engine and it's fuel management system. Things will make more sense with the basics in the back of your mind while you're working.

Everything that's used with your stock four speed will work with that five speed. That five speed is essentially identical to the four speed except for the fifth gear. You will lose the top gear switch though, that activates the solenoid for your vacuum advance. You can just bypass the solenoid to have vacuum advance in all gears. It's described in the Emissions chapter. If you replace any clutch parts, just make sure they have the same dimensions as what's on the engine now. Cheap parts that are easy to replace are the pilot bushing, and the front and rear seals on the transmission. If you're going to put a new clutch set in, you might as well do the rear main seal on the engine also, if you have the flywheel resurfaced. The super cheap swap would be to just move the shift lever over and re-use all of the old parts. You'll want to take some Scothbrite or similar to the main shaft to make sure the pilot bushing works right, and the clutch disc locates freely. Looks rusty. Don't forget to check the speedo gear. It will swap also.

Isn't the intercooler for NA drag-racing a bag of ice on the intake manifold? With the modern glass-filled nylon materials, you probably won't get the same effect but there are probably people cooling other parts of the intake ductwork.

Just forumizing. It's interesting to see how the path to "my engine doesn't run quite right" starts.

What did the valve control? In other words, what are you giving up with your simple "solution"?

Take a wheel in to a store. They'll probably let you test fit without buying. Make sure they don't stick out the back of the wheel or they won't clamp properly.

Isn't inline6 saying here that WPN-062 is the diesel pump? RockAuto is selling the -079. From the info link on Rockauto - More Information for AISIN WPN079 Alternate/OEM Part Number(s): 2101017S25, 2101017S26, 2101017S27, 2101017SY7, 21010V0725, 21010V0726, BA01017S27 Edit - maybe the WP079 is special after all. The other manufacturers all list the same part number for gas and diesel but the WPN079 doesn't show as a gas engine option. AISIN doesn't even have a gas engine option (1978 280Z example) Carry on and good luck...

I'm pretty sure that people use the early 280Z EFI tank in 240Z's when they switch to EFI because they want the internal baffles and the bigger fuel lines for the high-flow/pressure EFI fuel pump. Should work fine for a 260Z since it's in the middle. I'm just interpolating, no actual experience with a 260Z tank.

Why not just leave the electronic distributor and ignition module in? Why remove it for a points set-up then circle around to electronic again? It's already there.

It's kind of an unwritten principle on this forum that the type of work you listed is pretty much routine maintenance. On a Moderator's bad day you could probably get banned for even suggesting that you would pay someone to do any of that. It's all relatively easy, non-complicated work. All of it. Time and sweat required of course, but the only "specialized" tool you might need would be a spring compressor. Not kidding and not trying to run you down. It's all simple stuff.

Starting fine with the screwdriver in the electrical switch is a sign that all of the relays and wiring are correct and working, unless there's a heat related problem. Really sounds like the key just isn't turning the switch far enough. Take two pair of needle nose pliers, grab the metal piece with both, and twist the part in between. That way there's no load on the connection with the keyed mechanism. Visualize first to make sure you're twisting the right way to get more action from the key.

Are you sure they're 280Z springs? Are they progressive or straight rate? One coil is a lot. Look for numbers on them. 5022 is the 280Z number. If a coil was cut it would be obvious since the factory bends the final coil to fit the seat. They might be 280Z coils that someone cut to use in a 240Z. Documented on Hybtidz somewhere. Here- http://forums.hybridz.org/topic/88025-installing-tokico-280z-hp-springs-in-a-240z/

The Engine tuneup chapter, Checking and Adjusting timing, shows what you should be seeing as far as the adjustment lock-down screw. That's a screw head in a slot, between the arrows. And the Engine Mechanical chapter, page EM-25 (1976 FSM) shows what you should see down the hole with the distributor out, with a description of the side to which the tang should be offset ("the smaller bow-shape will be faced toward the front". It will make sense when you're looking at it. With no lock-down screw you can pull the distributor right out by hand.

Looks like your distributor is in backwards. The hole that would take the screw that went through the slot on the other side of the distributor base is covered. There are several ways that this could happen. I've heard that some people have been able to force the distributor in 180 degrees off, or your oil pump is installed incorrectly, or someone took the distributor apart and put it back together backward, etc. It does need to be locked down though. There are workarounds you could try or you can run through the oil pump and distributor installation procedures in the FSM to see what's off. Put the timing mark on zero and see where the distributor drive tang is oriented first (take the distributor out and look down the hole).

Strap your battery down before driving. You can make your own with parts from any auto parts store.

Pretty sure that only the Pope is allowed to do this.

The factory spec. for the 260Z was 8.8 CR. Regardless, you're still applying the paradigms from other engine platforms. Cranking up the CR alone does not do much. From what I've gathered, an appreciable bump in CR will not give a comparative increase in performance. It will make the engine more sensitive to fuel quality (octane rating) and more detonation-prone. It's all covered in this forum, here and there. Good luck. If you're looking to be unique just pick a powerplant that nobody's ever done and make it work.

Compared to the E88 (one of them anyway, I believe there were several variations), the E31 just bumps the CR from 8.3 to 8.6. Valves are the same size. Probably a faction of a horse or a ft-lb. gained. I'm going from ozdat's engine calculator so might be missing something, but it looks like the E31 is bathed in the glow of the mysticism of unavailability here. Happy to learn something different though, in case I see an E31 in the local yards. In general, there don't seem to be many simple stock part swaps with the L6 that produce big gains, like you find with other engine platforms. Easier to just swap a bigger engine. http://www.ozdat.com/ozdatonline/enginedesign/

Good link to some good work. Has anyone followed up with a USA L28E engine? Hate to be picky but that's what the OP has (probably, assuming nobody put a JDM engine in to his 76).

If you were on all-bacon diet you might get some beneficial surface treatment effects but probably not worth the time and/or effort. You probably are getting rods mixed up with pistons. The turbo engines have a different part number for both pistons and piston rings (Honsowetz and Monroe as reference). I don't know what the difference is. If you're going to tear down or refresh things before installing the turbo you night consider a "Hybridz best-practices" route. Do some work on the head unshrouding the valves, which will give a bigger chamber, lowering compression ratio and also give better flow to get the most from every pound of boost. Use an aftermarket EMS, like Megasquirt. Don't spend any money on the bottom end until you're sure the tune isn't going to destroy expensive parts. Etc. Take a few notes as you browse the threads and a good path will appear.

After reading the various cam destruction threads over the past few years, if I ever install a new cam I'll leave the rocker arms off and spin the engine with all valves closed before starting. Probably build a little aluminum foil shield to direct any spray then check each lobe for flow. Or even cut a plexiglass tube lengthwise to allow viewing as the cam turns. Confirmation of flow before applying any pressure to the cam or rocker arms. If it still gets destroyed at least the oil supply question will be clear. Inline, you could still do that if you haven't taken things apart yet or taken a sledge to it. It would tell you something.

Doesn't the unburned fuel from a miss skew the O2 sensor's reading to the rich side? If it's "false rich", adding fuel should make the AFR reading show leaner, as the lean misses go away.

If you can smell the mouse pee you'll probably want to hose it out with water. That stink will last forever.

The thumping noise is at cold start. It goes away and doesn't come back, I assume when oil is supplied. The other noise follows RPM exactly so doesn't seem like it would be a timing chain flopping around. That's why I thought it might be the wrist pin, after looking through Monroe's book. Removing the injector plug is a variation on his recommendation of removing spark. The motor has always had a ticking that remained after adjusting lash and I've kind of blown it off as just a noise that this particular engine makes, maybe from a loose mouse-trap spring or something. But I decided to find the source and here I am. Can't find it, except I know now it's associated with the #1 cylinder. Everything's adjusted, the mouse-traps all seem tight, the noise seems to come from somewhere besides the valve train. I've put about 10,000 miles on it so hopefully I'll get some more noise as it gets worse if it's about to go. I have another engine that will go in eventually. If I knew what to look for on the ticking engine I might take it out sooner and fix it. Thanks for the comments. The only blown up L6's I've personally seen all had rods thrown through the side of the block, but they weren't mine so I have no idea how much warning the drivers had. Mystery noises make me nervous.

For the money spent already, it probably would have been worthwhile to modify a valve cover with a plexiglass window to see what's happening while running. Might still be. Cold running only of course.