123 ignition for Datsun L6 on my L28

[AliK]

Blimey, belt and braces or what! Good stuff ...

Thanks dude, taking no risks given how fast it rotates on full chat

Nice job but are there any non- resistor rotor alternatives for you 123 distributor Ali?

123 themselves have realised that on other classics, such as TRs, the rotors fail after only a few hundred miles (as the one in the picture above had - it’s the one that came with it when new). So they have brought out a £40 rotor without a resistor. Apparently the added resistance causes too much HT stress on the rotor and cap.

Normally the resistor ones have Kilo-Ohms of impedance but the one I stripped and wired up had Mega Ohms. I will measure the Bosch one that is working in the car at the moment and post up it’s impedance later.

Yeh, surely there is?

Anyway I've seen rotor-arms like that but they had a centrifugal cut-out in them (where your fibre material was) to limit revs. Had one on my 1.7 (Porsche) twin-carb VW Camper. I replaced it with a normal one.

Now that is an elegant analogue solution! [emoji106]

 

[Rob Gaskin]

Ali, has your wife ever told you to stop working on that old car?

 

[AliK]

LOL too funny Rob!!! You know it! She calls it “the other woman”, but equally she married someone like her dad (complete with the cheesy jokes) so she has had a lifetime of getting used to it [emoji12][emoji1787]

 

[toopy]

Just throwing this in there as until seeing your 'modification' i hadn't even considered it, but,

at full chat with the rotor arm spinning at god knows what speed! could it become unbalanced and possibly start touching the cap?
reason being, that's quite a bit of extra wire and solder in there, and seems to me the shape of rotor arms is to balance out the rotating mass,
otherwise why bother with the rear wing arrangement?

 

[Rob Gaskin]

Just throwing this in there as until seeing your 'modification' i hadn't even considered it, but,

at full chat with the rotor arm spinning at god knows what speed! could it become unbalanced and possibly start touching the cap?
reason being, that's quite a bit of extra wire and solder in there, and seems to me the shape of rotor arms is to balance out the rotating mass,
otherwise why bother with the rear wing arrangement?

At 6000 rpm that rotor will spin 50 times a second!

Oh no he'll be filing the plastic down next!

 

[AliK]

Just throwing this in there as until seeing your 'modification' i hadn't even considered it, but,

at full chat with the rotor arm spinning at god knows what speed! could it become unbalanced and possibly start touching the cap?
reason being, that's quite a bit of extra wire and solder in there, and seems to me the shape of rotor arms is to balance out the rotating mass,
otherwise why bother with the rear wing arrangement?

I guess we’ll find out soon enough

That same thought did occur to me but I’m relaxed about it as I don’t think the weight is massively different and these things aren’r that accurately balanced in the first place. Besides the JB wouldn’t have gone all the way to the bottom. Should have weighed it before and after I guess

I’ll look for wear marks after installation and a good thrash! As it stands the local roads are flooded and she’s not gonna do much more than idle / warm up to test the old cap with new rotor and new cap new rotor.

 

[Timbo]

I appreciate that this is an older thread, but there is some really useful information here. So thank you.

I am looking to swap out my 260z distributor for one of these 123 systems as while the existing old electronic ignition has so far been reliable, I do have pinking issues at certain revs.
Plus it will be off for a Dyno as soon as I can get a slot (everywhere seems to be very busy since things started to ease) so it seems sensible to offer the tuner better tools with which to adjust things.

Question: Am I correct in thinking this does not need a vacuum supply?
I cannot see any reference to it on the product itself, but @AliK mentioned that his was retained. And connected where?
For reference I have Triple 40DCOE's fitted with a vacuum take off from the manifold to the Distributor, which I presume works.

Finally, as the last comment on here was from January this year, is there any further feedback on those of you that have fitted and driven with this throughout the Spring & Summer?

 

[AliK]

This thread exists so that people can ask questions and add to the body of experience, so thanks for posting.

There is indeed a vacuum sensor on the 123 and on the SUs there is a vacuum take off point on the front carb behind the butterfly.

On DCOEs you may find that the vacuum will flutter and may not be ideal / smooth at lower revs as I would imagine it’s coming from 1 cyl only. But if it works fine on your existing dizzy then that’s good news.

You can set the vac advance to start at any rev and vacuum reading you like.

I have VERY little vac advance on mine as I am still battling reversion at around 2.3 and 3.2 Krpm causing torque dips. This translates to very rich mix at these points, especially on the cruise. So the timing would be too advanced for the AFR.

My advice is to use an AFR in conjunction with the 123’s MAP (Manifold Absolute Pressure) sensor to decide how much and where you want advance.

If you have a modified engine, replicating the 280zx curve may not be suitable.

 

[AliK]

Ps. As for reliability, except for the first cap that lost it’s electrode, I haven’t had any issues. With any dizzy, I have always carried a spare cap and a rotor in the spare wheel well just in case. I also have a spare coil, a couple of spare leads and spark plugs.

 

[jonbills]

I appreciate that this is an older thread, but there is some really useful information here. So thank you.

I am looking to swap out my 260z distributor for one of these 123 systems as while the existing old electronic ignition has so far been reliable, I do have pinking issues at certain revs.
Plus it will be off for a Dyno as soon as I can get a slot (everywhere seems to be very busy since things started to ease) so it seems sensible to offer the tuner better tools with which to adjust things.

Question: Am I correct in thinking this does not need a vacuum supply?
I cannot see any reference to it on the product itself, but @AliK mentioned that his was retained. And connected where?
For reference I have Triple 40DCOE's fitted with a vacuum take off from the manifold to the Distributor, which I presume works.

Finally, as the last comment on here was from January this year, is there any further feedback on those of you that have fitted and driven with this throughout the Spring & Summer?

not to dissuade you from the 123, but your pinking is either a result of the distributor having too much advance or the head having too much compression. for the former, adjusting the current dizzy is easier than fitting a 123 and fiting a 123 can't fix the latter.

 

[AD240Z]

My Blue 240z has a 123 - i bought it that way from the PO.

Aside from deleting the maps and having to set it back up ( my stupitidy - but it didnt take long ) - i havent had any issues this summer .

It did feel a bit strange sitting in the car on my phone - ..... but it was relatively straightforward .

 

[Timbo]

not to dissuade you from the 123, but your pinking is either a result of the distributor having too much advance or the head having too much compression. for the former, adjusting the current dizzy is easier than fitting a 123 and fiting a 123 can't fix the latter.

Good points.
Maybe a proper tune up on a reputable Dyno will address both points.
It isn't exactly broken at present either, so I may exercise some patience and wait until I can get a slot.
Thank you.

 

[alienpoker]

So a brief update, my new cap arrived this afternoon so did a monsoon from the Amazon. So unable to pull the car out of the garage I set about getting rid of the resistor in the rotor...

Then soldered both ends and went a little obsessive, soldering the entire thing for reduced vibrations.

Finally added some JB weld to keep things from vibrating, provide more mechanical stability and get a decent finish on her ...

I’ve done all this as well. I actually buy the WVE 4R1209 rotor (for < $20) and start from there. It says ‘Made in Italy’ on the box and has held up well. You need to do this, especially if using CDI. I run a MSD6AL.

I actually like the 123/Tune+. I made over 300hp on an engine dyno with a stroker L28 (modified cam, pistons & head). Works for me so far...

 

[Rob Gaskin]

I have a new MSD6AL and dizzy in my garage. Do you have an adaptor for the tacho or did it work ok.

 

[alienpoker]

You don’t say the car. I expect it’s a 240Z from your profile picture. My experience is you need an MSD8920 tach adapter. That works with 123/ignition distributors and MSD6AL on a 240Z.

Without the MSD6AL installed, my ‘73 240Z tach worked correctly with a standard coil and the 123/Tune+ dizzy ...

With the MSD6AL, I had to remove the resistor in the 123i Rotor exactly as shown above and also bypassed the ballast resistor to get full voltage at all times. Then added the MSD8920.

Be aware that the very early Zs have different internals than the 280Z tachs. I’m not familiar with 280Z wiring, only 240/260... I’ve never owned a 280Z.

I think around ‘74 (at some point) Datsun supplied and wired the tachs without using a current-loop trigger. Looking at a wiring diagram should show this. So they may work without an adapter or using the MSD8910 if they are all over the place. I think that’s the source of much of the confusion.

Google: 240z-tachometer-working-with-an-msd6-series-ignition and you should find a wiring diagram.

 

[rcv]

I just installed a new 123Ignition unit in my 11/70 240Z and wanted to chime in on my install. I was really pretty nervous given the pictures of Ali's exploded muffler, but overall it went pretty smoothly. I spent a bunch of time trawling the forums for installation info and only really found various grades of horror stories, so I'm posting mine here as encouragement for anyone who wants to give this a shot.

1. Remove the spark plugs, and plug wires.
2. Remove the valve cover so you can look at the camshaft in the next step.
3. Using a big old ratchet on the cam bolt, rotate the engine until it's at exactly TDC. The 123Ignition install manual recommends that you actually put your engine at the "static timing location" (e.g. 10 degrees BTDC) but I followed Ali's advice and set it at 0deg. The rest of these instructions (particularly step 7) will assume that you've done the same.
4. Pull out the old distributor.
5. Put the included collar onto the new distributor, and insert the distributor into the hole. You can tighten down the 10mm bolt that holds the collar to the engine, but don't tighten down the Allen bold that holds the distributor to the collar yet.
   1. Note that while the rotor on my original distributor pointed towards the radiator, the rotor on the 123Ignition distributor points towards the drivers-side fender. Don't worry, this is normal.
6. Hook up the blue wire and the red wire of the distributor as per the instruction manual (this was pretty clear IMO), and turn your key just before cranking. You should now be able to connect to the distributor over bluetooth with the app.
7. Now comes the tricky part. The distributor can rotate infinitely in its collar right now, and if you try spinning it around you'll notice that the little green light will blink on and off at regular intervals during the rotation. I think this is kind of confusing, and not really explained well in the manual.
   1. Look at the rotor, and memorize the direction it's pointing. You can rotate the distributor body all you want, but the rotor will always point this direction until you crank your engine.
   2. Fit the cap onto the distributor and note where the little embossed "1" mark is on the top.
   3. Rotate the distributor until the "1" mark is aligned with where you remember the rotor pointing. You can pull the cap on and off while you're doing this to check.
   4. Pull the cap off and set it aside
   5. Lightly push the rotor CW to remove any backlash.
   6. Rotate the distributor slowly CW until the little green light turns on. Tighten down the Allen key on the collar to lock down your distributor at this angle.
   7. Refresh your memory about the angle of the rotor again, and loosely fit the cap back on the distributor. The rotor should be pointing directly between the #1 and #5 HT leads. Remember, this is because your engine is currently set at 0deg TDC which is well after your cylinder #1 should have fired. That rotor is now swinging its way CCW to the next cylinder (#5). I think this hangs people up the most, and it's a shame the manual does a terrible job of explaining it.
   8. If the rotor looks like I described above (pointing between #1 and #5) then you're good to go. Buckle down the cap to the distributor and say a prayer to the timing gods.
8. Connect the black wire on the distributor to the (-) terminal of your coil as described in the manual.
9. Put your valve cover back on, your spark plugs back in, and reconnect your plug wires and the lead from your coil to the center of the distributor. Your engine should be fully back together at this point
   1. Remember your firing order is 153624, so make sure you put your plug wires back correctly
10. Go into the 123Ignition app on your phone, and pull up the advance curves. The default advance curve was set to 0 deg advance at 500RPM on my unit when I got it. I think that's because of the weird static offset thing they want you to do. To get your engine to fire up, you'll need to immediately load in a new advance curve that has at least a few deg. advance at the start of the curve. I just copied Ali's curve he posted earlier in the thread, and it worked great for me. Make sure you hit the "Write" button at the top to flash in the new curve.
11. Say one more prayer, and turn your key another click. Enjoy!

Overall the install went very smoothly for me. The only issue was that I originally hooked up my plug wires according to the firing order in Tom Monroe's "How to rebuild your Datsun OHC engine" book, which is wrong! It's correct in the service manual, and in Ali's original post so just be careful there.

I just went for my first drive with the new distributor, and even my co-pilot noticed how much better the car runs. My only remaining issue is that my Tach isn't working now. I'm fishing for answers in a forum post on classiczcars - if anyone wants to jump in there I would much appreciate the help!

https://www.classiczcars.com/forums/topic/65113-240z-tach-wiring-after-123ignition-install/

 

[rcv]

Well after a little bit of effort I got the tach working, and everything seems to be running well.

@AliK would you mind sharing your latest mechanical and vacuum advance curves? I'm really curious what other people are running.

 

[atomman]

I will grab a picture of mine and upload it ,

 

[atomman]

Here you go , works alright in my over bored L28 with triple 40's

Still a work in progress though and always willing to listen to advise

 

[jonbills]

Here you go , works alright in my over bored L28 with triple 40's

Still a work in progress though and always willing to listen to advise

There appears to be a problem with your RPM limit Gary?