FastWoman

I think I read that some of the modules have a longer dwell to better saturate the coil. I'm wondering if those would be better suited for lower RPMs, though. Thanks for the advice about carrying a spare. I think I'll do that!

Andy, congratulations! Well, except for the radio... I had to laugh about your Blaster 2 coil. My own coil, also wrapped in rubber (an innertube), looks just like yours. I painted my bracket in black epoxy, though. I wish I had known about a volt meter adjustment. I actually had the thing pulled from my dash this afternoon. I was replacing all of my instrument panel bulbs while I had the dash somewhat apart. Too late now; it's all put back together. OK, get some sleep now...

No offense taken, Idaho. I admit the MSD is overkill for most applications, including mine. It did look nice under the hood, though! I have to say, in hindsight, that my experience is a lot like Walter's. I've completely redone the ignition in my car, and now it runs a LOT stronger. Everything I changed out seemed to improve the picture a bit more. The new distributor was maybe 20% of it. NGK plugs and wires were maybe another 20%. The new coil was perhaps 40%. The new ignition module was the remaining 20. Perhaps the ignition module proved to be a bit more important in the low RPM end. Dunno. Anyway, it made a world of difference. I'm hoping new injectors will do some good too. I'm not expecting miracles, but I do expect some improvement in fuel economy. I'm thinking that the injectors will pay for themselves over the next few years in fuel savings.

Dunno, Jan.... I've long been fascinated with once-beautiful things that have deteriorated, whether cars, boats, buildings, or even people. I enjoy looking past the deficiencies and appreciating the history of what was. I can look at a car in a wrecking yard and think, "how beautiful." I always see the possibilities for restoration. (Of course a car in a crusher is a different matter.) Honestly, J Shara, if you hadn't told me that was a 240, I'd never had known it. I won't comment on the car, because that pisses people off. Let's just say I think my own Z is a thing of beauty. Outwardly the only thing that has changed from the time it rolled off the assembly line is the Panasport wheels. (I have the original hub caps and wheels, though.)

Er, well, I guess you're talking about me. In my case, the MSD unit was to be a replacement for an OEM unit that was on its way out. I could get the MSD for less than a refurb OEM unit, so that seemed a better deal to me. My decision not to go with the module-in-distributor type design was based on difficulty with heat dissipation. Besides that, I already had a new/rebuilt OEM distributor and didn't want to buy another one. I didn't know about the GM HEI adaptation, or I might have done that first. It works great for a daily driver, which is what I have. If I were hotrodding, I think I'd still go for the MSD. I really have to say that I'm quite impressed with the vibrant spark the MSD unit generates. I mean, if the MSD unit won't ignite it, it can't be burnt! Peace, Sarah PS Cool factor DOES count, at least for some folks! It's not the family station wagon, after all!

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A quick follow-up: I finally got my car put back together and had my first good test drive today. I still get the occasional misses, although probably less frequent now. What I do notice, besides the tach not twitching, is that I've got a whole lot more low-RPM torque. I think I added about 500 RPM more useful range on the low-RPM end. Acceleration is much better too. Fuel injectors are the next job. I'm going with Standard Ignition injectors. I was strongly advised not to go with refurbished units. That sort of makes sense to me. Regarding the MSD-6A, I'm pretty confident in saying it's sold now.

I get you, Andy. It's sort of a Zen thing. ;-) I'm thinking of two possible approaches to the overvoltage issue. One would be a modified 60A circuit breaker such as used in household breaker boxes. It would come already with both thermal (bimetal strip) and overcurrent (electromagnetic throwout) protection. The electromagnet could be rewound with many, many more turns of fine gauge magnet wire and could be actuated by a power transistor with a zener diode on its base. The other approach would simply be a better warning system. I know that my own voltage guage is perpetually at almost full scale (16V), probably because of age and corrosion on the movement spring. I suppose it might go beyond full scale in an overvoltage situation. However, it wouldn't exactly jump out at me and grab me by the throat, screaming, "OVERVOLTAGE! SHUT DOWN NOW!" Maybe the solution is some sort of piezo alarm. That would be much easier to design and could be mounted anywhere under the dash. I'd be interested in hearing your thoughts in 20-20 hindsight, since you've been there and all. I'm beaming positive vibes your way, BTW. I methodically worked through my own frustrating several days with this ignition stuff. Nothing melted down, but it was frustrating nevertheless. Now I have a (better) running car. This morning I put a few things back together, and we'll be taking a beautiful fall drive a bit later. So yes, there's light at the end of the tunnel. Peace, Sarah

I didn't know these came in different varieties. How do they differ from each other? Mine was a $16 part from CarQuest. If anyone with a 280Z has been following this thread (or follows it in the future) and is a bit more adventurous than I am (willing to take more risks with the black-box ECU), I thought about winding some wire around the coil as a pickup to trigger the ECU. One side of the pickup coil would go to ground with a diode in series, and the other would go to the blue (-) coil wire (note: with the original IM disconnected and with the blue wire NOT connected to the coil, but just feeding the signal back to the tach and ECU). The problem I encountered was that there was so much stray electromagnetic flux from the coil that I really had trouble making accurate measurements with my oscilloscope. You have to keep all your leads very short, and even then, there was some weird capacitive effect going on that was giving me headaches. I was afraid to ground the oscilloscope more aggressively to the chassis, because it's one of those USB units. Blowing out the laptop computer with a voltage spike would be the nastiest outcome of all. If I had a more robust scope (e.g. an old Tektronix or some automotive oscilloscope), I could have tackled this project a bit better. Good luck to anyone trying to tackle this problem!

Andy, I've got to say I admire your positive attitude in the wake of your massive meltdown. I think my language would be much more colorful than yours. I'm absolutely amazed at all the damage that was done. Scary! I wonder whether there's some overvoltage protective device that could be installed on the alternator output to interrupt current if the alternator goes berserk.

Thanks, Dave. I looked through the posts and followed the links. I frankly don't agree with the approach and feel that the signal to pin 1 of the ECU could be a bit too... er... robust. The idea is that the 450VAC signal at the coil's primary would then be fed through another inductor, which would ring further. I think that could risk blowing out the wave shaping circuit of the ECU. It really wasn't the way the adapter was meant to be used anyway. This is simply a trial and error approach where, luckily, the engine ran for one person -- and not for another. On further reflection, I wonder whether the input stage of the ECU uses some sort of tuned circuit to pick up on the frequency of the oscillations at the beginning of the burn time and reject the oscillations at the termination of the burn time (which occur at a lower frequency). By contrast, the oscillations when driven by a capacitive discharge system occur at a different frequency still and are quite a bit shorter in overall duration. That mismatch could make the ECU very difficult to trigger. Anyway, as I said, I'm not going to use chewing gum and bailing wire for my Z. I don't agree with MSD's approach to this issue. Their system seems to be a very nice one that produces a very hot and robust spark, but I think it should only be used for a carbureted system -- or on an EFI system that can trigger off of a 12V square wave (e.g. the tach output). It would be great if they would redesign their system with trigger outputs for the EFI, but apparently they didn't think that far. I'm actually pleased with the GM HEI module. I mounted it to the back of a power transistor heatsink and mounted it offset from the captured nuts where the reluctor connector doodad was mounted near the coil. I had to mod the heat sink a bit, but it's actually not a bad retrofit. I don't know how long these things last, but at $16 a pop, I think I could replace quite a few of them. Yea, GM!

Hi Walter, Pretty much the same for the '78. I was only flooding because of the cold start valve. None of the injectors were firing. I thought about the multiple spark issue, but for that to be an issue, the EFI computer would have to track something like 30,000 RPM (and actually much higher). Needless to say it can't do that. The problem I was encountering with the trigger might have had something to do with burn time. I think the pulses were just too fast with the MSD system. Anyway, I have good news. I've installed the GM HEI module, and it works very well. The MSD is out and officiall for sale. Bids, anyone? I wish I had done that in the first place. Thanks, Andy, for the link!

GRRRRRRR...... I just can't find the magic juice that makes the EFI computer (a.k.a. black box) happy. It doesn't seem to use a simple voltage divider and/or clamp. I'm guessing there's a cap involved somehow to smooth out the peaks a bit. Anyway, I'm sure if I keep experimenting with it in a total information vacuum, I'm bound to find some way to make it very unhappy -- irreversably so. Considering that, I give up. Anyone want a good deal on an MSD-6A in like-new condition? Some wires are clipped short. I guarantee that it sparks just fine and would be the perfect upgrade for a CARBURETED system. Anyway, I put everything back to stock for the moment. It runs as before. (Yea! Nice to hear it run.) I'm about to go fetch an HEI unit for the conversion that many have used on HybridZ. Yes, I realize I could use the HEI to trigger the MSD, but I'd also have to get the adapter coil to trigger the EFI and the tach, and that's just too much chewing gum and bailing wire for my car. I won't do it. More later, as this drama unfolds....

If you go with an MSD-6A ignition module (my current project, as you've apparently read), it will trigger just fine off of points, and you won't have the same EFI trigger issues that I'm having. The tach trigger might be an issue, but I'm guessing their $50 adapter would work for you. The points will last just about forever if all they're doing is triggering the electronic ignition. The only caveat is that they will (very) slowly wear down (but not burn). You might have to re-time every once in a blue moon. Just make sure your vacuum advance actually works. That's apparently the first and most common failing of the Z distributors, both points-style and magnetic. I don't know if the GM hack is the best way to go, but it's certainly not the ONLY way to go. Just laying out options for you...

You're in LA? Then when you go north... TAKE HIGHWAY 1! Don't question it. Just do it. It will quite possibly be one of the most beautiful drives of your life -- and a FUN drive in a 280Z! And plan to spend a bit of time walking around the Monterrey/Carmel area. Look on a map, and see where 1 skirts the coastline. It's a very tedious and not too rewarding drive towards LA. It's at its best from Monterrey and Carmel on up to San Francisco. I can't tell you where it makes its transition, though. There are a lot of cool little towns along the way, some of them right out of the old surfing movies -- except more modern now, of course. Don't miss a single mile of that stretch of road! Be there! Oh, and the Muir Woods are a must-see thing too. Absolutely amazing!

Good luck! You might want to flush all of your injector connectors with LOTS of water and give your car a day to dry out before starting it again. Put a lubricant on the connectors before reattaching -- preferably dielectric grease or silicone grease, but if not that, then at least a shot of WD-40. If your connectors are pretty hopeless, you can find replacement connectors on Ebay for around $20 for the set. You'll of course have to wire them in. I think they'll require connectors on the harness end. In fact that's my next project after ignition. I have new injectors, connectors, holders, and seals on order. The injectors I have are kinda scary. Two have been replaced by the PO (piecemeal) and the others have crackly little hoses on them.

I agree with your friend.

Nah, I don't think I'm expecting too much. It's their business, after all. They should collect installation data on quite a variety of models -- at the very least the collectable ones. I'm not sure I expect them to know how to deal with an old Skoda or anything running off of a 6 V system. But a 280Z? Sure. Anyway, I tried the 12V tach output, and it won't trigger the FI. :disappoin I've decided that you really can't get there from here with the equipment they offer, without installing a working OEM ignition module (or the GM hack) AND their $50 tach/FI adapter. Their adapter seems to be little more than an inductor that will ring at a higher voltage necessary to trigger the FI and tach (like an ignition coil without the secondary winding). Without the adapter, the output of the OEM or GM ignition module won't exceed 12V. That's a lot more "stuff" I have to install and a lot more $$$ too. I hate grossly ineligant solutions and am astonished that that's all they offer. Anyway, I think you're right about being able to trigger off the coil. However, the voltages are higher, and I don't want to fry anything. My next step (since I refuse to keep spending money and buying components to create some collosal Rube Goldberg contraption) is to make my own adapter to drop the coil voltage and clamp any voltage excursions below GND. I'll then feed the output of that device to the wire that would go on the negative terminal of the stock coil. That should make everything happy. I'd have done that this afternoon, except that I got involved in a driveway earth-moving project and ran out of light. Tomorrow's project! If anyone has any of these answers, it would help me greatly: (1) What is the peak positive voltage ordinarily on the negative terminal of a stock ignition coil when everything is working correctly? (2) What is the ignition voltage trigger of the FI computer? That is, what voltage to the #1 pin of the FI computer triggers the thing? (3) What is the input impedance of the FI system's ignition trigger (i.e. pin #1) (4) Does anyone actually have a schematic of the fuel injection computer? I don't mean the wiring to it, but rather its innards. Thanks! Peace, Sarah

FAIW, I did the headlight upgrade when I did because I was already into the harness with the MaxiFuse, alternator wiring, and grounding upgrades. Fewer connections and shorter wire paths mean fewer problem points and better current. Anyway, whatever solution you try, good luck with it! I know you'll be thrilled with the outcome. Peace, Sarah

OK, you have a '77 -- one year different from my '78. I THINK the fuel injection is the same. Here's what you can do to test your injectors and their connections. (I did it yesterday on my own car.) BTW, it's up to you to verify you have the same configuration of system. I'm not taking any responsibility for anything you might blow out by following my advice.: Pull off the driver's side kick panel. The fuel injection computer is underneath it. With your ignition off (!) pull the big connector off the front of the module. You'll have to push a little catch near the cable to release it. Twist it around, so that the connections are facing you. You're looking at the connections to all fuel-related devices in your car, including the injectors. As it hangs down (cable at top), you'll see a longer row of connectors on the right and a shorter row on the left. The connections are numbered from the upper right #1, to the lower right #18, and then from the upper left #19 to the lower left #35. Now find or make a little probe you can use. One end will connect to ground, and the other end will be small enough to touch briefly to a contact ON THE CABLE SIDE of the connector. (I want to be clear -- leave the fuel injection computer alone. You're only testing at the big connector that clamps to it.) Hook up a fuel pressure gauge, and turn on your ignition. You should see the system pressurize. Now use your probe wire to briefly actuate the individual injectors. Watch the pressure gauge to see if the pressure drops off. I would only touch/tap each connection BRIEFLY, as you want enough pressure to test all your injectors. Now, using the numbering scheme I described, you do the following: Jumper the following to ground to watch for fuel pressure bleedoff: Starting on the righthand side, 4th from bottom, and moving upwards: #15 (cyl 1) #14 (cyl 4) Then starting on the lefthand side, 3rd from bottom, and moving upwards: #33 (cyl 2) #32 (cyl 3) #31 (cyl 6) #30 (cyl 5) If they open and bleed off fuel pressure, then they're at least working. That doesn't necessarily mean they're working *well*. If you think you might have a weak connection that gives you an intermittent problem, you can also measure resistance through the system. However, it's a bit more difficult. BTW, this is where your wiring is more likely to differ from mine, but resistance testing is pretty gentle -- nothing to blow up. Here's what you do: Disconnect your battery. Find your Electronic Fuel Injection Main Relay inside that big black box on the righthand side of the engine compartment -- the one that the fusible link boxes are mounted to. It has a rectangular 6-wire connector on it. Pull the connector loose. Contact #43 on the connector is the one you want. Clip one wire on any of the aforementioned injector connections on the EFI main connector, and probe each of the six connections to the relay. Only one of them will have any continuity. Now start measuring resistances between that one terminal and each of the six injector contacts. The resistance will include about 6 ohms for the dropping resistor, located beneath the brake master cylinder, as well as the resistance of the injector coil. I don't know what that resistance is, but you should have the same TOTAL resistance on all six tests. If you don't, then you might have issues with a connection or with the drop resistors. You can always pull the drop resistors to test them. Mine measured 6.5 ohms, but they are nominally 6 ohms each. Similarly, you can pull the connectors on the injectors and measure those individually. If you have extra TOTAL resistance that you can't account for, then you probably have a bad connection somewhere. Whew! I hope that helps. Peace, Sarah

Nice install. Thanks for the link! Hopefully I won't need to go the Rube Goldberg route, but in case I do, it's nice to know I can do it with something so cheap and ubiquitous. After sleeping on it, I think I'm just going to try the 12V square wave tach output to drive the EFI. I figure I'm not going to hurt anything. After all, the EFI computer has seen MUCH, MUCH higher voltages from the (-) side of the ignition coil. What's an itsy bitsy 12V square wave by comparison? Either it will work, or it won't. If it works, then good. If not, then I'll probably look for an HEI IM to trigger the MSD unit, the tach, and the EFI. This really seems like a dumb way for MSD to have designed their system. Did it not occur to them that some people might buy the unit to replace/upgrade a dead/dying OEM electonic ignition module? Then again, maybe they already have this capability,m and their tech support doesn't know it. I really don't have much confidence in the kids with MSD's tech support. They sound very much like the ubiquitous neighborhood kids who drive lowered Hondas with loud mufflers and primer paint jobs -- the type that usually wires a bunch of stuff together and twists the distributor around until the engine runs and makes lots of noise. (I actually hear one of them outside right now!)

I can't help you with OEM coil configurations on a 240, but I'm currently working on a conversion to the MSD 6A ignition. (You had asked about electronic ignition.) This unit will trigger off of either points or a pickup coil, and it is designed to work with the Blaster 2 coil, as it should. I'll have pics of the install before too long, but as a preview, it's a pretty easy install. I moved my coil to where the (now very rotted) service light used to be, just in front of the brake master cylinder. There's a heat shield bracket there (at least on the '78 280), and the coil bracket can be bolted right on top of it. Then there's space where the coil used to be for the 6A ignition module. It's almost a bolt-in install. I made two aluminum rails to bolt into the old ignition coil captured nuts, and the base of the ignition module screws into that with self-tapping screws. For stabilization, the end of one of the aluminum rails (or two, if you so desire) brackets into the shock tower with a hole I drilled there for a sheet metal screw. (I HATE drilling holes in the body and will avoid it at all cost, but I found I did need to drill that one.) MSD's unit isn't an obvious upgrade to the electronic ignition I already had. Mine was simply getting feeble and somewhat random. However, it's an excellent and obvious upgrade to points, at least if you're going to drive your car very much. If it's a fair-weather, weekend-drive sort of car, I'd just keep the points (personally). BTW, here's a link someone gave me to a cheaper electronic ignition upgrade: http://www.zhome.com/ZCMnL/tech/gmhei.html The cost of that person's upgrade was about $100. However, it included a wrecking yard 280 distributor. I'll caution you that almost every distributor in a wrecking yard will have a frozen up breaker plate, and I bet the breaker plates are frozen on most of the Z's still on the road. You can go with a rebuilt 280Z distributor for around $100 and probably turn in your 240 distributor as a core. Autozone Duralast distributors carry a lifetime warranty, BTW, which might be useful with the problematic vacuum advance design.

OK, back on the phone with MSD tech support. I asked what signals could be used to trigger the EFI from the MSD 6A. They said it can't be done. The configuration I'm supposed to use is to have the old OEM IM read the signal from the reluctor and pull the (-) coil wire to GND with every trigger. That signal is fed to the MSD6A through the white wire to trigger it. The signal also triggers the EFI. The only problem is that my OEM IM is a bit weak. I suppose I could use it to trigger the MSD6A, but instead... Couldn't I trigger the EFI off of the tachometer output, which is a 12V square wave? BTW, Paul, the tach/EFI adapter you mentioned doesn't do what we're thinking it does, at least according to MSD tech support. They say I can't get from point A to point B without a working OEM ignition module.... but I don't entirely believe it.

Paul! Yes! That's it! THANKYOUTHANKYOUTHANKYOU!! Yeah, I had checked fuel pressure -- OK Ignition -- OK (runs off of starter fluid) Mildly flooded from the cold start valve, but not what I expected. Continuity with the injectors -- OK Could actuate the injectors by grounding them individually Pumped up the system by running the fuel pump, juiced the intake with a healthy shot of starter fluid, and started the engine. It ran for maybe 5 sec. Fuel pressure dropped a bit, making me think (again), "AHA! It's squirting fuel." Then I remembered the fuel pressure regulator just doing its job. So I juiced the intake again, started again, and the fuel pressure held steady. No injection because... (and here's where you filled in the missing piece) ... Nothing was triggering the fuel injection computer! :stupid: Given that, do you think I can simply hook Nissans's negative coil wire back up to the neg side of the coil for the trigger? Is that safe for the fuel injection computer? Thanks again, guys! Peace, Sarah

Hi Andy, I hadn't heard that one! That reminds me of the fashion rage at one time -- Mercedes hood ornaments worn hanging from a chain around the neck. Of course they were broken off from people's cars, not purchased from dealerships or wrecking yards. Regarding the antenna, I just meant vandalism -- most commonly bending them over, but sometimes pulling them outwards to strip out the mechanism. For some sad reason, people tend to do this more to cars that are "different" -- especially nicely restored antique cars. People are just plain mean. I remember once about a month after I had sprung for a new paint job for my old '75, someone left a "ping" (crater, really) in the door more than 1/4" deep. I'm guessing they used a hammer? Another time when I had left my car sitting in the driveway a bit too long (maybe a month), someone decided to add sugar to the gas tank. I had to rebuild the head. People are truly unbelievable. They delight in ruining a good thing. The only good power antenna is a fully automatic one.