NewZed

Page 150 of Cramer and Hoffman's Performance Fuel Injection Systems book describes a situation where electrical noise from the starter caused crankshaft position sensor signal loss.

Pretty sure those numbers are in the Front Suspension chapter. I just made mine really tight. The nut clamps down on two washers and a metal sleeve, on a shoulder of the rod, so it's all metal on metal. Use Loctite.

The EFI harness in the early 280Z's is essentially completely separate from the the rest of the body harness. It even has its own fusible link. You can unplug it without chopping any wires, leaving all of the other car functions intact. I have one from a 78 in my garage, no cut wires. Search for threads dealing with switching to carbs. You won't really be modifying anything, just adding a few more loads. Some relays, a power supply wire, and grounds, are all you need to focus on. If you find yourself getting ready to chop a wire, you're probably making a mistake. Some of the guys on classiczcars.com have put together some really nice full color wiring diagrams in .pdf format that would be handy for you. Much easier to deal with than the photocopied FSM diagrams, or the paper FSM. Don't think in terms of "chopping". Chopping is bad.

Spark strength is a possibility. If you're seeing a spark from the coil then you're getting a trigger and the ignition transistors are breaking the circuit. Weak spark could be from dwell time on the ignition set too low. You should really post your MS settings so one of the Megasquirt guys can get you closer. You're making progress but could take a wrong turn at any moment. If you can't save a file just do a print screen to an image editor or use the Snip tool in Windows accessories to get a screen shot. Your hardware seems to be working, it's your software that needs help.

The distributor rotor spins inside the cap. The spark jumps to the closest electrode. You should always have spark at the spark plugs. Timing is when it happens. Connect the timing light to a plug wire and see what happens. Injectors don't get spark. They get grounded so that current can flow, opening them so that fuel can squirt. To be ignited by the spark, if it happens at the right time. Some people don't want to bother with terminology but the words are the only way to describe what's happening, or supposed to be happening.

Why are talking about spark to the injectors, and how do you know you have "spark" from the coil to the distributor? Spark travels from the coil to the distributor cap to an individual electrode and down the wire to a spark plug. One at a time. There will be no spark from the coil unless it has a place to go. It has to end up somewhere. It has nothing to do with timing, spark doesn't care what time it is.

That's the power wire to the 1978 EFI system, with the fusible link intact. There would be a red wire with the opposing white connection on it from your harness, to plug in to, with the original EFI harness. By the way, you didn't mention anything at all about a different engine in the car, so I just guessed based on your other statements.

Here's another, same idea. 1975. You must be looking at early Z R180 pictures. Attached a 1973 picture for ref.

Show some pictures. A variety of parts flipped, turned and spun, and off by 1.5 - 2" is hard to visualize. And you didn't say if you have an early 260Z or later. Small bumper or big. Also, I've noticed that Nissan used "transverse link" to describe several things. If you mean the curved link between the uprights, that shouldn't affect where the nose of the diff ends up. It looks like there are two TTT bars, one R180 and an R200. Maybe you have the wrong bar. https://technotoytuning.com/nissan/280z/mustache-bar-datsun-240z-260z-280z

I had the clunk for a while and decided that the actual noise is not from the nose going up but when it drops back down. Lift-drop-clunk. A new stock diff mount along with the snubber might do the trick. The ES mount is convenient though, since it will let the diff hang by itself and is nice if you do any work on the suspension. You can remove the cross member without worrying about the diff. U-joints can cause noise with just a little wear. They're hard to diagnose without prying them around with a lever and examining with a good eye under good light.

Here's an old thread that describes what some people do. The ES mount is flat and will rock on the nose of the diff. They remove urethane from the center-bottom mount to let it seat on the mounting holes. Another way is to stack washers under the mount at the holes but the original RT design already lowers the nose of the diff, since he designed it for a small block chevy transplant application. In an ideal world there would be another RT-style mount that holds the diff in the L6 orientation. Forgot to say that the ES mount holes need to be elongated also since they don't line up with the diff holes. Also described in bjhines's thread. A good round file will do the job. Actually a good size round file will probably do both jobs. http://forums.hybridz.org/topic/50209-ron-tyler-style-front-diff-mount/

*sigh* I feel for you Six_Shooter. It's so obvious now. Hard to believe that the brain-washed masses accomplish what little that they do. Now that you've shown the way, some will be sure to follow. Cheaper, easier, better - how can they not. Thanks for the enlightenment.

Still sounds interesting. But you haven't offered anything very specific The links were helpful. Can you do some simple math to show that the Delco EMS can be up and running "for less money" as you stated. You've made a proposal but it needs support. Just saying. Our own stuff always seems like the way to go. Until the math is done. I think that you and one other person are the only ones using the Delco system on an L6. Seems like it should be more popular.

Thanks for the links. It would be great to see a general path laid out to a Delco ECM running an L6, with some links and cost estimates. Just to make the case that there's another option out there than Megasquirt or one of the high dollar EMS. I browsed through your links and there's a lot there but they are very computer geek oriented (no offense). You have to get deep in to chips and EPROM's and communications, etc. to get anywhere. Megasquirt is making their money by being easy to get directly in to running and tuning with good support. I'm sure that Matt Cramer is on more boards than just this one, but he is available and has good insight on how to make things work. If you could lay out a plan to get running with a tunable Delco ECU that would be noteworthy.

The Delco ECM option sounds interesting but where do you get the products to tune it and how is the support? Do you flash the board directly or have to buy a daughter board like Nistune?

This web site is pretty informative. It shows that they're all the same until July-August of 1976 build date. http://www.carpartsmanual.com/datsuns30/DatsunZIndex/Brake/RearBrake/tabid/1734/Default.aspx

No need for the part number. Just pointing out that JWT Z31 ECU could be one of many possibilities. Even 84 turbo has four model numbers. Also implying that there is no guarantee that the PO knew what he was doing. People install large injectors all the time thinking that more gas = more power. And there's no way to notice no info on the JWT site for your older ECU because it was never said that it was an older out-dated ECU. It's not apparent that you've been on the site, or actually talked to someone at JWT, you didn't say. It looks like you have more information than you've shared. Post it up. Not many people talk about the JWT products, they're a mystery even though they've been around for a while.. The O2 sensor is only really in play during cruising conditions. Probably not the cause of your flames.

Maybe the PO installed super-duper 440 cc Supra injectors to go with the JWT modified ECU. Lots of different ECU's under the "JWT Z31" category. A lit of part numbers will help you out in the long run. Know what you're working with. http://www.jimwolftechnology.com/customer_results.asp Here's something useful - http://jimwolftechnology.com/wolfpdf/280%20Z31%20450HP%20UPGRADE.PDF

Your new injectors have a different, newer style of nozzle. I've seen it on a few other brands, like BWD and Standard (yours are probably one of those brands). Your new injectors aren't designed to use a pintle cap. The tender pieces are recessed inside the injector tip, protected. As far as directions on what to do when increasing injector flow, those would be in your SDS instructions. Lower injector open times would be the main change.

IF you're just looking for stronger spark the MSD can be run from your 1973 points distributor. If you're looking for more adjustability in your advance curves the Mallory might offer that. The simplest, cheapest way to get stronger spark might be a 280ZX distributor with its electronic module. You can get them for about $125 from Rockauto or your local parts store. Not shiny and don't have a big brand name attached but pretty effective. Don't forget that a new distributor will come with different centrifugal and vacuum advance curves. The curves have a big effect on driveability and power.

I thought JMortensen would be pretty good at evaluating quality. He's been deep in to the details on his other car. Good luck.

How did you miss this one - http://forums.hybridz.org/topic/118434-1970-rolling-chassis-suprisingly-light-rust/?do=findComment&comment=1110416

Don't know if this will help, but I measured voltage on the four pins to my 1995 Pathfinder CAS, with it disconnected from the distributor and key On, and I get one ground wire (zero), one 12 volt, and two 5 volt. The Pathfinder has the same type of optical CAS with a high resolution and low resolution trigger out. So the 5 comes from the ECU. The "trigger" might just be the phototransistor grounding the circuit. I think that much of what is written about the "trigger" voltage coming from the distributor may be mis-guided or wrong.

You're not comprehending...

The fuel pump is not supposed to stay on unless the engine is running. On early cars nothing happens until you hit Start. Later cars had a priming function controlled by relays and/or the ECU. You need to know what is controlling your fuel pump power.