Zed Head

80 and 81 could have different ratios. There's also a reverse lockout mechanism that was introduced about that time. Generally, the casting numbers and letters have been found to have little meaning, despite conjecture about date codes and stuff. I have five. Nobody has shown that they could take a casting number and actually use it for some specific purpose, that I've seen.

Piano wire is a type of heat-treated steel wire. It's a "thing". The good hardware stores carry it, it's actually pretty common. The one I got was better than the factory wire, I thought, Very stiff. https://en.wikipedia.org/wiki/Piano_wire Getting a used part from a wrecking is a good idea. You have to look a little harder to find a long enough wire though. Most newer cars are more compact and don't have their valves far from the actuator. I went through this search when i was modifying my heater water ****. I think CO did too.

There's definitely a market. Pick one and sell it, or put a price on both and keep the one that doesn't sell first.

By identifying the guy as a "noted Z engine builder" you're placing suspicion on every noted Z engine builder out there. Doesn't seem right to do that. Better to just ID the guy and let him explain what he was doing.

We beat the heck of of the thermostat question about 3 or 4 months ago. It's probably in one of the 7 previous pages.

I made a new cable from hardware store piano wire. The hardest part is cushioning the edges of a pair of pliers so that they don't nick the steel when bending the ends. If it nicks, it will break instead of bending.

Apparently they make a sealed battery with a vent hose, for inside the car applications, like in the trunk (BMW's). Found a Carquest link also about venting, but there's a bunch of odds and ends links out there also. Can't find a battery that's labeled as "vented" but it may be that the vents are there on most batteries and just need to be opened up. Check the first link, it has some good information. I went and looked at my spare battery and it has two holes on the side like he shows, but I can't tell which are open (didn't try very hard). Yours probably does too and you could just rig a up a vent hose as he does, he even gives a BMW part number. The explosive gas problem is a real one though, along with corrosive gases. His fix is easier than venting the box itself. http://www.rtsauto.com/battery-venting-fitment-and-options-for-most-bmws-and-particularly-e30s/ http://www.bimmerfest.com/forums/showthread.php?t=396536 http://www.yuasabatteries.com/faqs.php?action=1&id=12 http://www.carquestprofessionals.com/batteries/faq_myths.html#9

Don't forget to provide air exchange to remove hydrogen gas. Explosive at low concentrations.

You can see the end of the actuating cable and what it's supposed to be moving if you stick your head up under the dash and look behind the glove box. Do that and move the lever, and you'll know which end of the cable has the problem. That's how I discovered that mine was bent, behind the face plate. Somebody got angry and forced it. Edit - also, not uncommon to find that people have blocked or bypassed the hoses because the core leaks. Sometimes they do it in the engine bay, sometimes in the cabin.

The fire ring is the hardest part of the head gasket and would determine how far the head is from the block and pistons. So that's where you'd want to measure, for clearance calculations.

Good deal. Better check at higher RPM also to be sure the Sense wire is connected to the regulator, and the regulator is regulating.

Yes, that would be a place to start. If it works you can modify it for safety and/or appearance. Jeff G has already done the experiment for you, described above, 10 days ago.

Could you stick a piece of plastigauge in the spark plug hole and squish ti to determine the distance? Something like a piece of weed wacker cord might work also, depending on how elastic it is. Just thinking... I measured my factory stock fire rings on my used HG and they came out to 1.25 mm. I don't think the fire rings are very elastic.

I think that he means #14 here - http://www.carpartsmanual.com/datsun/Z-1969-1978/engine-280z/engine-mounting The part number shows some possibilities on the interwebs. They're available, or were, in urethane also. Man, the site is old-dog slow loading up a page. I almost forget I clicked on Edit by the time it's done doing whatever it's doing.

Ah.. to be 16 again... Them RB's is spendy motors. https://www.google.com/webhp?tab=ww&ei=dq5PVNe5B8j8igLU9ICABg&ved=0CAMQ1S4#q=rb20det&tbm=shop

That's a good find. The N42 page, the first that you showed in Post #4, shows the intake seat changing in 6/75 (fairly close to Nissan's Bulletin), and the exhaust at 4/76. So a 75 might have harder intake seats, but probably not exhaust. My 1/76 build would have the harder intakes, but soft exhaust. I put about 20,000 miles on that engine and didn't have any problems. I think I rechecked lash at 10,000 miles. Seemed like it had never been off, it's out of the car now.

My mental summary ends up at "hot carb boils or vaporizes fuel in bowls, boiling fuel leaves via jets, unmetered". The basic principle of the carb's float bowl is a placid calm pool of fuel pushed in a controlled fashion through precisely sized orifices. Bubbling, vaporizing, recondensing fuel screws everything up. But the basic idea of all of these things and Nissan's obvious work, and their modifications, and writing up a whole book about it, and attempts to explain the concepts is "heat is bad for the carbs, avoid heat". That's the message, I'd say. Remove and avoid heat transfer to the carbs. Heat is bad. Heat is the enemy. See a path for heat to get to the carbs - remove it. Is more testing necessary? Heat, heat, heat, heat... Just joking around. Seriously though - the key is to remove the things that transfer heat to the carbs.

As noted, the FPR's all regulate to the same pressure. The ports are different, but otherwise they're the same. Considering the work done, and the fact that three valves were out of their adjustment range, a check of the wipe patterns would be a good idea, wouldn't it? The FPR problem might be saving your engine. Don't run it until you give it a good inspection.

That's actually normal behavior. Nissan started putting both inches and mm on the X axis in the 1973 FSM's if you want to look at a few curves with those units.

Price cut in half. $3500 now - http://portland.craigslist.org/mlt/cto/5808738675.html

The image attached is how Nissan explained it, in their 73-74 Fuel system Modification Plus manual.

Seems like a normally closed switch that opens under vacuum would be the way to do it. Have you checked continuity across the pins? Looks also like it's just asking to be taken apart and examined. Looks snapped on.

Generally people seem to say that the harder seats didn't show up until the N47 head, I think. But Nissan does mention hardened seat materials in the 1976 Service Bulletin. Seems like if they reported it in 1976 then the engines before probably didn't have it. I'd say "unlikely". If the valves and seats wear your valve lash will close up. That could be a maintenance check to do, to head off problems. Edit - might as well post the words in. Pictures below.

You won't really know what needs replacing until you get in to it. If the cabin has been dry the ECU should be fine. The injector quality will depend on the fuel that's been sitting in them. If the fuel pump and FPR were in good condition when it was parked, the system could have stayed pressurized for years. The connectors on the wire end are simple to replace. Rossiz put a lot of effort in to getting his EFI right before he switched. He didn't switch to carbs because it was bad. He's your best bet for getting parts that are known to be good. If you can determine what you need maybe he'll break it apart for you to save shipping costs. I imagine he has the EFI intake manifold sitting in his garage with the rail, injectors, FPR, linkage, etc. all still assembled on it as it was when it was on the engine.

Everyone told you to do this. Did you do it yet?! Nothing will change until you change something!