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Arne

Electronic ignition - Revisited after I gave up!

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Like the title says, I've given up.

Over the past 2 years or so, I've wasted a pile of time trying to get electronic ignition into my 240Z. And I've failed. I could never get anything working well enough that I could be happy with it.

I've tried two different ZX distributors, a total of three different E12-80 modules, a Pertronix ignitor in the stock 240Z distributor, and four different coils (original 240Z, original ZX, new aftermarket ZX & 3.0Ω Pertronix).

It's worth noting that all three of the distributors I've tried had good vacuum advance units and no slop in the shaft bushings. Good, solid dizzies.

I've fought pinging from bad advance curves, ignition washout at higher revs, and sometime both. I've swapped plugs, wires, cap, rotor, etc. around several times in a concerted attempt to make this work. (It probably doesn't help my confidence in this knowing of at least three E12-80 failures in the past few years around these parts, either.)

Try as I might, I haven't been able to get anything to work as well and trouble-free as the stock points. I'm not an idiot, I've been working on and restoring old cars for decades. But I've certainly failed here.

Yes, I'll concede that a good electronic ignition should be superior to the stock points. But for a weekend GT touring car, the points are probably good enough.

I'll also concede that considering how many people have made this work on their cars, perhaps my car itself is at fault. (Perhaps too much voltage drop at the ignition?)

But on the other hand, there's plenty of threads here with people having issues with electronic ignition conversions, so maybe I'm not alone. At this point I'm not convinced that either the ZX ignition or the Pertronix are the answer. Maybe the Mallory Unilite is better, but that's too much money for a stock L24.

I'm still open to suggestions. I've got a Pertronix Ignitor and 3.0 Ω coil sitting on the bench right now. If someone can give me a clue, maybe I'll try again.

Or not. It's running great on the points right now....

Edited by Arne

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Well, I am definately no expert, and I share your frustration when it comes to not understanding certain parts of the car, but I put in Pertronix into my 73 240 without a problem. Maybe its because I have so little experience so I followed the directions to a T, but it works great. No more problems with the points. I think you should give it another try. Pretend you are me and dont know what you are doing. :) I am happy with the Pertronix ignition.

IMHO, Chris

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I think you should give it another try.
Done that, several times.
...so I followed the directions to a T...
Yup, analyzed and followed them carefully. More than once. It's a simple device, not much to screw up there.
No more problems with the points.
I guess that's part of the problem. I've never had any problems with points. They work great, better than the EI systems. Cars used points for decades. They are also simple devices.

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Wow...I can relate to this LOL.

At least you got yours to run. I can't figure out where I' going wrong. Like you said...it's so simple but...I can't even get spark.

If you're happy with points and don't feel any need to go electronic then by all means put the points dizzy back on.

I'm not giving up. Yet... ;)

What was your reason for wanting electronic ignition?

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I would suggest disconnecting the vacuum advance and running the car at about 18 degrees BTDC timing at idle and see how that floats your boat. I got really good mileage like that with SU's. Add MSD for even better mileage and you don't have to use the E12-80 module, just run the module built into the MSD.

The one thing I didn't see you mention is jumping the ballast resistor. It should run with the ballast in place but you'll get a lot hotter spark with it bridged. Having used both quite a bit (first Z had points) I wouldn't run a point distributor unless it was absolutely necessary.

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I will always run the points system on this car. It is the only system I know, its simple and it works. I thought about the change over during the refurbishment but it wasn't plug & play so it was out. Anything to do with wiring is out of my comfort zone.

Bonzi Lon

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Ignition setups can be quite frustrating at times to setup and debug, as those are the only electric circuits in a car (from the seventies at least) which depend on electric signals which change their state rapidly in a short timeframe.

Anything else, including an alternator, can be relatively easy checked and maintainted just using a multimeter or even a test light, but with ignition setups you need to take care of the different signals, voltage/current levels over the time and the timing of signals itself - which is something you can't really see just using an multimeter, so this, IMHO, is the main source of frustration when trying to find a fault in such a setup.

In an ideal world where you would have access to a distributor tester, scope and ideally a current clamp, finding a fault in a ignition system is quite straightforward and not that difficult if you have done it before, but most people maintaining their own car understandably don't have access to these tools.

Still, with a multimeter, spark tester, a digital timing light and a bit of patience you can find most issues, thats the good news! Happy to post general testing procedures if this is of interest.

Points are the simplest solution and the easiest to understand and to fix, if you are comfortable with the maintenance (setting dwell, advance weights etc). The only real limitation is the maximum primary coil current of ~4A and points floating at high RPM (typically starting at 4-5K). As Arne said, not a problem for a weekend GT. But for a high revving sports car this can be a real limitation to get maximum power and full combustion at each cycle. A badly maintained points based ignition setup with undersized wires or the wrong coil type will act as a rev limiter and lead to a sluggish throttle response when accelerating, even if your distributor advance curve is perfect.

A good transistor (electronic) ignition can handle up to 8A easily, so no ignition fading at high speed and with the more advanced constant current (e.g. dwell control) electronic ignition you'll have the base for a reliable combustion at any RPM, air temperature and fuel mix (if air, fuel and timing are ok). Transistor ignitions can be driven by points or magnetic/hall/optical triggers, the later setups adds timing precision but also complexity which can make it hard to find and fix faults.

The Pertronix Ignitor I conversion is quite handy as it integrates the contactless trigger and the transistor ignition in one small unit. Unfortunately, there is no current and dwell control (the type II and III is reported to have this), and depending on the coil you are using the outcome can be quite mixed. IMHO, the Ignitor I is a great unit for converting a non performance oriented car which revs up to 4-5K, but for a sports performance car (such as the 240Z) you might want to consider a different approach or use the Ignitor I as a trigger for an MSD 6A box.

My personal recommendation for a six cylinder engine performance ignition setup is a conversion based on the Lumenition Optronics optical pickup driving a Bosch 0 221 100 137 electronic ignition, this combination has no fading up to 9K RPM and is quite robust. I have installed this setup in quite a lot of cars over the last years, and none failed yet. As the parts are made in Europe they might be difficult to source in the US though.

IMHO, electronic ignitions are more complicated but quite worth the effort.

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I've been working on Z's for quite a while now and just noticed that the 240Z dizzy #1 position is 60 degrees off compared to the 280Z's so when I switched from a petronix installed 240z dizzzy to a known good 280Z one I couldn't get the car to start till I removed the two scews that limit how far you can turn the dizzy and just turned it till I got it started but I also found my timing mark on the other side of the crankshaft did some research and read something about timing marks on air conditioned vehicles were on the oposite side of the crankshaft.I ended up repositioning my distributor drive to get my dizzy to point to #1 at TDC.If you compare a 240Z distributor cap to 280z you'll notice #1 on one is on the left of the clip and on the other it's on the right which is 60degrees off.I also tried moving my wires 1 post over but in my frustration decided to do it right starting off with everthing at TDC.Hope this helps you out.

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What was your reason for wanting electronic ignition?
Just the standard things. Hotter spark, less need for choke, faster starts, and less maintenance. Nothing critical, and nothing that's worth the fussing around that I keep doing.
The one thing I didn't see you mention is jumping the ballast resistor. It should run with the ballast in place but you'll get a lot hotter spark with it bridged. Having used both quite a bit (first Z had points) I wouldn't run a point distributor unless it was absolutely necessary.
Tried with and w/o the resistor in virtually all situations. In all cases, it worked better with the resistor bypassed, but still not as reliable as the points.

Oh, to be honest, I can't say that I won't try it yet again. After all, I already own the stuff, eventually I'll convince myself that there must be a way to get it to work.

But the most consistent problem has been spark wash-out at anywhere from 3500 RPM on up, the exact point it fails depends on what other config I have running at the time. Things like ballast or not, wide or narrow plug gap, which coil, etc.

It's worth noting that while I've seen this failure-to-rev complaint now and again with the Pertronix, I also experienced it with the ZX dizzy. This is what leads me to believe that the root cause is my car, not the ignition per se. The most likely theory in my mind at this point is my car has too much voltage drop at the ignition coil and such.

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I've been working on Z's for quite a while now and just noticed that the 240Z dizzy #1 position is 60 degrees off compared to the 280Z's...

I don't know about the 280Z, but the 280ZX distributor does have this characteristic . I pulled the oil pump and repositioned the distributor drive shaft to resolve the alignment issue.

Arne:

There is nothing intrinsically wrong with running points, so long as the distributor bearings are in good condition. As you state, cars used them for years. The only real down side is increased maintenance. If the car isn't a daily driver, and the points are working for you, why switch?

I know nothing about the Pertronix. It wasn't something that I was interested in pursuing.

The ZX distributors typically do have too much vacuum advance, at least in the later years, and since the only breaker plate that is still available from Nissan is for the 83, there is a strong risk that a rebuilt earlier distributor may have excessive vacuum advance as well. So your choices with the ZX distributor are:

1. Mechanically limit the vacuum advance to no more than 15-17 degrees

(at the crank)

2. Disable the vacuum advance altogether.

(See jmortensen's post)

Either approach will prevent the spark knock so common with the ZX "upgrade".

When using the ZX distributor you should jumper out the ballast resistor, and use the ZX ignition coil as well. I also notice that there are after market ignition modules from some of the generic parts stores for $100 - $150 each. If you are going to carry a spare, why not carry a cheap one?

But if your points distributor has good bearings, and the timing is set correctly, the relative improvement from electronic ignition will be difficult to notice.

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I would suggest disconnecting the vacuum advance and running the car at about 18 degrees BTDC timing at idle and see how that floats your boat. I got really good mileage like that with SU's. Add MSD for even better mileage and you don't have to use the E12-80 module, just run the module.

Always thought you needed the module to trigger the MSD this sounds pretty trick,how do I do it?

As for the ZX upgrade I dropped mine in and have had great starting and power across the band.

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The only real down side is increased maintenance. If the car isn't a daily driver, and the points are working for you, why switch?
That's the point I've come back to now. In fact, I've spent far more time swapping ignition parts around over the past two years than I would have spent maintaining points. After all, I only drive it 3-4000 miles per year. How much maintenance would points take for that period? Not much.
The ZX distributors typically do have too much vacuum advance, at least in the later years, and since the only breaker plate that is still available from Nissan is for the 83, there is a strong risk that a rebuilt earlier distributor may have excessive vacuum advance as well. So your choices with the ZX distributor are:

1. Mechanically limit the vacuum advance to no more than 15-17 degrees

(at the crank)

2. Disable the vacuum advance altogether.

(See jmortensen's post)

Either approach will prevent the spark knock so common with the ZX "upgrade".

Had the detonation issue been the only problem with the ZX for my car, I'd have probably gone this route. But the detonation was only part of the issue. I still experienced the failure to rev out with the ZX ignition - indeed the revving problem was lessened if I retarded the timing so the detonation became a minor issue for me.
When using the ZX distributor you should jumper out the ballast resistor, and use the ZX ignition coil as well. I also notice that there are after market ignition modules from some of the generic parts stores for $100 - $150 each. If you are going to carry a spare, why not carry a cheap one?
Yup, that's how I ran it. Both with a used original and a brand new ZX coil. The spare module I carried in the car came from a 210 in the local pick-n-pull, paid $10 for it. It worked fine, and got my friend back home when his module failed without warning at a Datsun show. I think it is still on his car running great even now.
But if your points distributor has good bearings, and the timing is set correctly, the relative improvement from electronic ignition will be difficult to notice.
My thoughts exactly. At this point I figure I have better things to spend my time on.

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Oh, to be honest, I can't say that I won't try it yet again. After all, I already own the stuff, eventually I'll convince myself that there must be a way to get it to work.
Oh, I know myself so well. Today I put it all back.

Decided it was time for a minor tune-up today. So as part of that I decided I'd try it one more time, and give it every possible chance to work.

So I installed new plugs (NGK BP6ES), new wires (not that the old ones were bad, but I'd couldn't handle those bright blue NGK wires under the hood of my red car any more), cleaned, tested and lubed the advance mechanism, installed the Ignitor and matching 3.0 Ω coil, bypassed the resistor, and built a new, heavy-gauge power wire to the Ignitor. Set the timing to 8° BTDC, vacuum advance still hooked up.

So far, so good. Seems to pull smoothly to 6000+ in first and second, didn't drive it anywhere I could try it in the higher gears. So I'll give it another try for a while. Updates will be posted when/if things change.

Edited by Arne

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Arne,

Glad to hear it's running. I had a friend who had someone else put in his electronic ignition, actually it was a Z shop, and they never bypassed his resistor. He drove from Tampa to dallas and back. He stopped by my place to see if I could figure it out. Once we bypassed the resistor the car ran noticably better. I set my car to 10 degrees BTDC with the vacuum advance disconectted ( I am running fuel injection though). May I also suggest NGK 5632 which is BCPR6E-11. The "C" means it's the smaller socket size. Drppoing the "S" changes from a standar tip to a V groove and the "-11" increases the gap to 1.1. These are a standard honda plug, so everyone usually has them in stock.

Jim

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I had problems with my ignition too, and the more I "improved" it with upgraded parts the worse it got. In the end it turned out a few of the connections on the keybarrel were dodgy. Just to be sure, now I run a relay with the coil +ve getting a direct feed of juice from the battery.

Do Zs run a relay?

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Oh, I know myself so well. Today I put it all back.

Decided it was time for a minor tune-up today. So as part of that I decided I'd try it one more time, and give it every possible chance to work.

So I installed new plugs (NGK BP6ES), new wires (not that the old ones were bad, but I'd couldn't handle those bright blue NGK wires under the hood of my red car any more), cleaned, tested and lubed the advance mechanism, installed the Ignitor and matching 3.0 Ω coil, bypassed the resistor, and built a new, heavy-gauge power wire to the Ignitor. Set the timing to 8° BTDC, vacuum advance still hooked up.

So far, so good. Seems to pull smoothly to 6000+ in first and second, didn't drive it anywhere I could try it in the higher gears. So I'll give it another try for a while. Updates will be posted when/if things change.

Arne: I put my Pertronix in over three years ago and it still works just fine. Running the same Ngk plugs you are,Beck Arnley Cap,Rotor,and Beck Arnley 7mm wires. Left the stock coil in as well as the Ballast Resistor and really changed nothing out. Timing is about the same as yours. My distributor is the original,far from completely tight, and probably needs to be rebuilt. Original Motor has over 250k and is using some oil. Still runs fine. I do run premium gas from Chevron. Only problem I have ever had is pinging once in awhile. And yes this was after two E-1280 failures. Anyway I try to keep things as simple as I can and it works for me. I am a shadetree mechanic at best.:laugh: I know how particular you are about your car. Just cannot understand why it won't work for you. Gary and Roger helped me and I have never looked back. I am planning on putting a New/Oem/ Rebuilt distributor in this summer,and having my original rebuilt. No magic here. Alot of guys seem to run different types of ignitions and if they work for them I say very cool. If you like your points and are happy that is all that really matters is it not? Or not. Just my opinion.:D

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Well, my best guess as of now is that the Pertronix will work fine in most cars, but only if everything else in the ignition is good also. The differences between what I have installed now and working fine (so far) and what was failing to rev past 4500 RPM when I last went back to points are two small things: 1.) I replaced the older BP6ES plugs with a fresh set; and 2.) I made up a new power supply wire to run to the Ignitor that was much larger gauge wire than the previous wire, hoping for less voltage drop to the Ignitor.

That's all I did differently, yet this time it's running fine. The jury is still out on this, as I don't yet trust it to stay this way.

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Wasn't sure whether to add this here or put it under the what I did this weekend thread. Seems it would be most appropriate here.

This weekend I went to the pick your part place in Oceanside and snagged a 280ZX dizzy to replace my Petronix/standard dizzy. I too had the 4000 RPM stall and was hoping this would fix it. At 4K, it seemed like the ignition was cutting out and I could actually get a gas smell, so I was thinking it was an ignition issue.

The change out was pretty easy since I already had the Petronix. I pulled the old dizzy and mount, noted the rotor location (cylinder 2) and installed the new 280zx dizzy and mount and started the cabling with rotor location being cylinder number 2.

This worked great, started right up. Odd thing was the RPM's would go up much higher than my other dizzy. Had to break out the Unisyn and lower idle speed. The thing that is odd here is if my earlier dizzy was optimized, and I think it was, why would a new dizzy bring the RPM's higher?

Anyway, I have the dizzy dialed in and I love how it runs. No more 4K stall and maybe just me, but car seems much smoother. I will keep the old dizzy just in case, but for now, it seems like a nice change. So for my Yellow '71 240 Z, I am now running a 280 alternator and 280 dizzy on a 260 motor. Talk about a hybrid.

Edited by motorman7

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This worked great, started right up. Odd thing was the RPM's would go up much higher than my other dizzy. Had to break out the Unisyn and lower idle speed. The thing that is odd here is if my earlier dizzy was optimized, and I think it was, why would a new dizzy bring the RPM's higher?

A higher advance at idle will lead to a higher idle RPM.

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This worked great, started right up. Odd thing was the RPM's would go up much higher than my other dizzy. Had to break out the Unisyn and lower idle speed. The thing that is odd here is if my earlier dizzy was optimized, and I think it was, why would a new dizzy bring the RPM's higher?

I agree with the above. Double check the timing at idle. If you are going to run without vacuum advance (which I suggest) then start with the timing at about 18 degrees BTDC and adjust a little back or forward from there as necessary. If you are going to run the vacuum advance I would guess that you will probably have too much total advance. Depending on which ZX distributor you have you will get 17 to 18 degrees of mechanical advance out of it by about 2500 rpm, plus whatever you get via the vacuum advance. Those vacuum units are almost always broken too.

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Me three. I ditched my ZX dizzy because I didn't like the advance curve. Knowing what I know now, I'd have just ditched the vacuum advance instead.

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I will give that a try. Right now I have the vacuum hooked up. It will be interesting to see how it does with the vacuum removed. Will try and set that up tonight when i get home. Thanks for the input.

Rich

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OK, I am now running the 280ZX dizzy without the vacuum input. This is a good set-up. I get less or no ping under load than when I had the vacuum hooked up. Also, motor freely revs to 7K, which is great. No more 4K flat line. Afraid to take it over 7K as I think the tach has a slight lag and could be at 8K during a rev.

So I am doing about 75 MPH at 3K RPM. Theoretically I could do over 150 MPH in this thing before redline now. May have to try that someday to see what it could really do.

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