NewZed

The GM HEI transistor ignition module (look for 1977 Camaro ignition module at the parts stores) is cheaper ($20 +/- range) than the MSD unit or the Crane, but it takes more work to get it installed right. The links describing the connections for a 280Z, and a 240Z with a later electronic ignition are below. Basically, one side of the module hooks up to the pickup coil in the distributor, and the other side connects to the positive and negative terminals of the coil. Grounding is through the mounting hole on the module. One option if you're on a low budget, or your current setup is all buggered up. I installed one on a 76 280Z, using the stock coil and resistor and leaving the wire from the coil resistor negative terminal (which came from the wiring harness) unmodified, to maintain the signal to tach and ECU. No wires cut or spliced, just two jumpers from the coil to the module, and the distributor wires moved over. The original ignition module is just unplugged (as described in a separate writeup from Atlanticz.ca about the E12-80 distributor swap - another option for you guys) and kept installed as a spare. It performs essentially the same as the original module, but it's about 34 years newer. Be careful that you know where all of your wires currently come from and go to as they might have been modified in the last 30+ years. The Zs that run carbs could be wired up completely independently of the wiring harness, for troubleshooting or just better functionality, except for one switched power source (which could even be a switched hot wire from the battery if you wanted to avoid the ignition switch). You would lose your tach signal though, but that could be wired in separately also, using the wiring diagram for your model. 280Z GM HEI - http://www.sonic.net/~kyle/hei.html 240Z GM HEI - http://www.sonic.net/~kyle/ztech.html Nissan E12-80- http://www.atlanticz.ca/zclub/techtips/distributor/index.html

You might have a bad damper or missing Woodruff key (the key that locks the damper to the crank, is it in there?). Apparently the rubber can go bad allowing the outer metal ring and pulley to slip. #2 looks right for cam and crank alignment, both valves closed, piston at TDC. But the notch should be at zero on the timing mark. You can look at the injector or intake runner to see which valves are intake. They are in line with the intake valve with the cam lobe directly above.

When?

My comment was really directed at anyone that discusses detonation, not your comment specifically. I agree completely, all RPM matter because that's what driveablity and overall performance is about. I think a lot of this discussion gets diverted by a focus on peak HP numbers. I've seen some good articles in the past on average power under the curve versus peak numbers, and how that is a more meaningful measure of engine performance, but the forum discussions on high CR always seem to drift back to peak HP. Flat torque curves, part-throttle driveablity, etc, get pushed aside. I think that one of your responses in the past was about increased power across the rpm range, improved driveability, etc. I was hoping to direct things back to that perspective. All I'm hoping for is more detail than "10:1 Cr, 32 total advance" gave X peak HP, or similar from anyone who has actual experience running high CR. More details on driveability, the pros and cons of high CR, did they run a "normal" timing curve or ignition map, and how they are making it work.

I was wondering when this topic would pop up again. One question I've been left with in these discussions is, what are the specifics of the timing and where in the rpm range does the rattling occur, when it does? Since Megasquirt seems to be very popular, maybe a timing v. pressure and rpm map would tell the story. Or the basic distributor specs. if one is used. I ask because I have been mucking around in the area of distributors and timing and ignition modules recently and have found a very large range of possibilities for variation in "stock" timing curves, mechanical and vacuum, from the variety of factory distributors used in the Zs over the years. So every time I see 28 degrees or 36 degrees total, I wonder "when"? When is the timing all in and when does the detonation happen? It seems like, especially with something like Megasquirt, that instead of reducing your total timing if you were on the edge, you could move the curve up the rpm range. Anyway, I think it would add some useful detail to this interesting and recurring topic, and maybe add some clarity too.

Start at about post #20 in this thread and things should make sense - http://forums.hybridz.org/index.php/topic/96568-alternator-question/page__pid__909445__st__20#entry909445

Here's an assortment. Maybe your year is in there... http://www.datsunstore.com/advanced_search_result.php?keywords=heater&osCsid=49f67b9492386999c5c38b5de2a1d552&x=0&y=0 Start here if the results page I linked to doesn't hold up - http://www.zspecialties.com/

There is an 81 Maxima with an apparently fully intact L24E in the Portland Oregon South Pick n Pull, Row 34. In case anyone is interested. I assume that it has the popular Maxima N47 head (forgot to confirm, what else could it be). The engine looks complete and stock with no hack work visible. The distributor stator magnet is broken, maybe that's why it was junked. It looks like it was running recently otherwise. Watch out for the mouse living in the hood lining.

You can't go wrong here - http://www.xenons30.com/reference.html The EE and ET chapters will tell you a lot about your timing. The TPS is covered in EF. Once you get these figured out, you'll probably have more problems to work out so it's best to have this on hand. Kind of surprising that you rebuilt the motor but you're new to ignition timing. Just saying, it's interesting. How did you rebuild the motor without the FSM?

A couple more options for stock parts - http://www.zspecialties.com/ http://www.courtesyparts.com/

Atlanticz's site has a few wiring diagrams. Looks like the 240s run positive to the coil through the tach. You might be able to jump across the tach plug to get power to the coil or run a temporary wire, if you really need to start it. Be careful. http://www.atlanticz.ca/zclub/techtips/electrical.htm

The guys on that madelectrical site cover what bjhines is saying (Edit - sort of, no offense), plus a little more, from a different starting point, and add some funky pictures. It's an interesting topic, especially with all of the old crimped splices buried under the typical Z's harness tape. These guys suggest a common central terminal to run all of your loads from, plus put your sense wire there. Seems to make sense, although I'm sure there's better looking hardware out there. If my stock 280 harness wasn't in good shape, with low voltage drops, I'd probably tear it out and go with the central distribution point. Second edit - This would allow the shortest, direct path to any new accessories, with dedicated fuses. http://www.madelectrical.com/electricaltech/remotevoltagesensing.shtml

Thanks rayaapp, I appreciate it. I see that this one has the super high vacuum advance. Kind of scary. And the dual vacuum advance curves (dual vacuum ports from what I've gathered), which I assume are switched some how. Not really clear yet on how that works, I would guess rpm based (Edit - just found something similar in a ZX FSM. Apparently it's an emissions control thing, with a cold, warm, normal position - strange). Thanks again.

I need a spare distributor and have located one from a 1981 Maxima with L24E and automatic transmission. I have downloaded every manual from the Xenon site so can find curves for almost all of the Z engines, but can't find anything similar on the internet in the 810/Maxima world. Does anyone know where this information exists or does someone have the information for the 1981 year? I'm looking for mechanical and vacuum advance numbers and when they happen. Thanks for any help.

Ignition timing is one of those hard to understand areas that is made more difficult by the way the distributor data is reported. As I understand things, the distributor turns at half crankshaft speed because the spark is only needed on every other up stroke. But the distributor data is reported in distributor shaft revolutions, so must be adjusted to tell you what is happening relative to the crankshaft. Therefore, the rpm reported should be doubled, because the cranksaft is going twice as fast as the distributor. And the degrees reported must be doubled, because the crankshaft travels 2 degrees for every one that the distributor does. The vacuum level is the same. So your L24 D606-52 specs would be: Mechanical starts 900 rpms ends 2000 rpms with a total of 12° Vacuum starts 100mm Hg ends 245mm Hg with a total of 11° With static at 10, you should get 33 degrees advance above 2000 rpm with over 245mm Hg (high rpm cruising) and 22 total at WOT above 2000 rpm. Your data is close to that, with wear and gummed up weights as possibilities for the 2 extra degrees and the higher rpm. But it looks like you had vacuum activated for both data sets. This is my current understanding and I welcome any comments about whether it is right or wrong. It seems to work for me, I have a DCF5-02 in my car with 17 (8.5 reported at the dist.) mechanical at 2500 rpm and 18 (9 reported at dist.) vacuum at 11.61" (295 mm) Hg. I'm running 17 static, so I'm at 52 and 34 (Edit - SHOULD be at 52 and 34, I don't have the right timing light to confirm), cruise and WOT, above 2500 rpm. I've heard not a knock or ping with 89 octane, but it is kind of cold here. I worked my way up a few degrees at a time and the engine got more responsive every time. I have a stock 1976 with EFI, but using a 1978 distributor. I'm just throwing all of this out there for conversation, and might be repeating something already well-known, or maybe even wrong. It took me a while to figure out what was up with the various distributors and how the specs. were reported.

I'm just a rookie myself, and don't even have an AFR gauge. But 16.8:1 AFR looks like you're running out of fuel, in addition to timing issues, if that AFR is what you are seeing when you open the throttle. Edit - I don't have much experience with carbs either so can't offer any solutions, just an observation.

The "cranking" circuit should be fairly simple to follow out. It just puts power to the small wire on the starter, when you turn the key to Start (it does a few other things but that's the basics). The ignition circuit is on when the key is On, that's why you can start an engine by putting a car in gear, rolling it and engaging the clutch, with the key at On. You can also short the big terminal on the starter to the small one (temporarily) to get the engine to crank, or start if the key is On (make sure it's not in gear if you try this). If you find that the car will start by shorting the starter, but can't figure out the wiring problem from the ignition switch, you could wire in a push button starter, either temporarily or permanently. Start at the small wire on the starter and work your way backward if you're having a "cranking" problem. p.s. I had a Start problem for a while when my key would not turn the "insides" of the electrical portion of the ignition switch far enough to hit Start. I had to bend the little tab at the back of the switch in the direction of rotation to get it do its job. But see if you can short your starter first before you go to that. Edit - the above is for go 260z's problem. It sounds like HakosukaJD has something else. 9V at one side and 0.5 at the other side, all the time, sounds like you have current flowing, which should only happen when the ignition module tells the coil to fire. Otherwise it should just sit there at 12 and 12. You might have a short between the coil and the module. Or a bad coil (maybe). Was your coil getting hot while you were measuring? I'm no electrical wizard so use these ideas carefully... I can take a beating if someone wants to shoot me down.

That's good information bjhines. I was probably confusing things with my one vs three comments, since "one wire" alternators can have multiple wires. The whole "one wire" thing seems like marketing buzz, I don't really get it. If you have a three wire setup in your car, all of the modern technology is there to be used. Why go backwards if you have it? I'm pretty sure that you can hook your S wire to the B terminal on a regular three wire alternator to turn it in to a pseudo one wire, then just rev your engine up every time you start it to get it charging. Anyway...

It sounds like you have all of the parts right in front of you. You could take some measurements. Look at the differences. You didn't refer to any search results either, from here or elsewhere. I'm pretty sure that I have seen this topic mentioned in the past. If you show what you found when you searched, people will usually help you fill in the blanks. You're just offering a blank piece of paper, to be filled in from scratch. That's no fun...

A few simple guesses suggest that you probably put a carb in there somewhere (to improve over "EFI crap"). Maybe even a different engine (although you didn't post under a swap forum). I just took an EFI harness off of a parts car last week and I seem to recall some distributor and coil wires in the vicinity. Did you look at the wiring diagram and make sure that your ignition module/distributor/coil circuits are still intact, and have power? Or at least trace it out so that you know it should work? The ignition module is in the cabin over by the fuse box on the passenger side, up under the dash. You probably disconnected an important wire.

There's no benefit to one-wire over three-wire in operation, as I understand it. One-wire is just two wires easier, but you lose a few things when you're done. The link below is kind of hammy but it's pretty descriptive. Scroll down a half-page to see the pros and cons. If you don't run a good voltmeter, or at least wire up your ammeter (you're back up to two wires already) with your one-wire alternator, you'll have no idea if it's working right (unless you're really tuned in to your fuel pump buzz and brightness of lights). If you're building a race car it might be the way to go, but long-term dependability is nice for a street car. Easier is rarely better (unfortunately), no offense intended to the one-wire camp. http://www.madelectrical.com/electricaltech/onewire-threewire.shtml

So you're implying that you had misfiring injectors before and the new connectors fixed that and gave almost 10% extra fuel mileage. That is worth following up on. Was the car misfiring or stumbling before? Does it run smoother now? Type and year of car and engine would be useful too (can't find it in your profile). I'm interested. More details would be nice. I still have the original, cracking, loose connectors on mine, although they have been cleaned up (low budget). Edit - Just noticed 280Z in your title. My mistake.

The Body Electrical (BE) section has drawings of all of the relays, in their locations. http://www.xenons30.com/reference.html The wiring diagram here looks pretty good. Opened in Firefox, you can zoom in and scroll around on the gif file. http://atlanticz.ca/zclub/techtips/electrical.htm

Page EF-8 in the FSM describes the fuel pump safeties. Alternator and oil pump switch. Use vise-grips, pliers and a vise if you really want to see what's in your filter. You really should check fuel pressure anyway, just as a typical maintenance check of pump, filter and lines (pressure drops), and fuel pressure regulator. Borrow a gauge if you can if you don't want to buy one. You're not getting a lot of replies here, because this is 101 stuff, and you're on the grad level site. Download the manual and start reading, it's full of good things. The Engine Fuel section is the best.