Stock Dizzy ign control ?

[Nismo280zEd]

For some reason I was under the impression I had to convert my dizzy to use CAS in order for the MS to drive the ignition. 78 280z. After reading a lil bit the MS says that it can control ignition event with a points dizzy.

 

Any body using the stock Z dizzy and running ign control?

-Ed

[randy 77zt]

if you had stock 78 280 z ign it will fire the megasquirt no problem-you just need a tach signal at the negative side of the coil.most people use the megasquirt to control the ignition timing because they are running turbo engines the need a well controlled ignition advance curve.my ms is fired from a hall effect sensor and magnets installed in the flywheel.the it uses a 81zxt distributor and 81 zxt transistor /coil for spark.but the engine is turboed.i have A 77 dizzy with a modified advance curve that would be great in a na car.

[Tony D]

Yeah, if you want to trigger the IGNITON through a software upgrade such as MS-n-S then you will need to modify the dizzy so it doesn't advance---it needs a fixed signal. Most people just swap in the 280ZXT CAS, but removing the advance mechanisim and using a fixed advance plate. Many things will work as Randy Suggests: Magnets in the front pulley, in the flywheel, reluctor of the stock Electronik Dizzy modified for no advance, etc etc etc...

 

If you are running fuel only, the points distributor with some modifications to the filtering circuit on the tach pickup section of the MS (Dave Capacitor) to use the points trigger for the fueling-only portion is all you need...

 

if you go with a flying magnet setup, you can use the stock distributor to distribute the spark---you just want to lock the advance mechanisim so you have the ECU controlling advance. One of the advantages of the later 280ZXT Distributors is a redesigned rotor allowing a more consistent rotor-to-cap tower phasing for computer controlled spark. If you use a magnet trigger, the 81 Distributor would be all you needed for that advantage---it's nothing more than a cap and rotor, and fits on the stock distributor drive.

[z-ya]

If you are running a basically stock NA L28, it really is a waste of time to control timing through a distributor. The amount of timing control is limited, and there really isn't all that much to be gained as far as power. You are better off setting the max advance of the stock disty just before detonation. If you are going turbo, then that is different.

 

Just conntect the MS to the - terminal of the the coil, do the "Dave Cap" mod from the MS FAQ, and you will be off and running in no time. At least get the motor runnig with the stock ignition first to debug the MS. You can always add ignition later if you decide to go turbo.

[Gavin]

Forgive me but I'm just getting more and more confused as I read.

 

Yeah, if you want to trigger the IGNITON through a software upgrade such as MS-n-S then you will need to modify the dizzy so it doesn't advance---it needs a fixed signal. Most people just swap in the 280ZXT CAS, but removing the advance mechanisim and using a fixed advance plate. Many things will work as Randy Suggests: Magnets in the front pulley, in the flywheel, reluctor of the stock Electronik Dizzy modified for no advance, etc etc etc...

 

So can I or cant I just get rid of the advance mechanism on my stock dizzy to use it with megasquirt? Is there a way to use it with the - coil output to trigger it or what is the easiest way at this point?

[Gavin]

MSnS (distributor) mode allows you to control your timing if you have a single coil firing a distributor.

Your tach/rpm signal into the Megasquirt can come from a crank trigger or from a "locked" ditributor using hall, inductive VR or opto sensors.

The code requires ONE trigger per spark event. If you have a multi-toothed wheel such as 36-1, 60-2 or a Nippondenso 24/2 CAS then you need to look at the wheel decoder instead.

 

OK nevermind I get how it works now, a lot better at least. So the bottom line is I can use my stock dizzy I just have to modify it with a hall or whateverelse? So basically then I should just go with the CAS dizzy.

[Tony D]

You guys (ED and GAVIN) are putting words in the mouths of the people answering the questions. neither of you have sufficiently answered any of the questions posed to you about the proposed setup you are running.

 

Let's recap thusfar:

What Megasquirt requires is a Crank Referenced Signal that will trigger three events per crankshaft revolution. This can be accomplished through the 81 CAS unit, magnets on the flywheel, magnets on the pulley, or hall effect sensors in similar configuration.

If you reference off the cam, to give the same 3 per revolution, you will need six triggered events. This can be accomplished off the stock 82/83 CAS which has a specially splined drive to keep slop to a minimum.As before, six trigger magnets, or paddles on the camshaft with a pickup can also be used.

You can also use a stock distributor that has had both the Vacuum and Centrifugal Advance Mechanisims removed and the breaker plate locked to prevent any movement. If you are using the reluctor and pickup in the stock system, you will need to interface through the stock MS Box through an amplifier to shape the signal (HEI Module). This is IN ADDITION to the HEI module you will use to triger the coil for the spark events. I needn't be anything special as there is no dwell issue or high output required like on the one that drives the coil.

 

But points? No, I wouldn't recomend points as the signal is simply not clean enough totrigger the events. If you converted to a pertronix or other breakerless ignition system then you could use it. But for the cost, an 82/83 ZXT CAS would be available.

 

So to sum it all up, POINTS, no. Breakerless, yes, with modifications.

 

If you have N/A, there really is no real need to control spark with the ECU---it's when the turbo kicks in boost when spark control comes in handy. For my wife's 260Z, I went with the MS-n-S on an N/A simply because the ignition system was breaking down, so a conversion to the 82 CAS had more than one advantage.

 

Keep in mind, if you ARE turbo, the extra voltage of the spark flying around in the distributor can cause issues with tower jumping---which is one of the reasons the 81-83 ZXT's have terminals spaced further apart, a rotor that fits the cap tighter, and a rotor with a longer arc for spark jumpoff to a terminal...

 

If you are turbo, and plan on boost above 10-12psi, you woul.d be well served to go with the cap with the wider terminal spacing and not use the N/A dizzy in that application.

[Guest 280ZForce]

If you are turbo, and plan on boost above 10-12psi, you woul.d be well served to go with the cap with the wider terminal spacing and not use the N/A dizzy in that application.

Now...what if u r using MSD on a 81 turbo motor w/ MS? Right now, i have my 78 dizzy hooked up and dont know if i should change over to a zxt dizzy or not. i have the 81 dizzy still, but the shop said the n/a 1 works w/ the MSD and what not just the same or something. i'm gonna find out details tomorrow on it when i pick up the car.

[Nismo280zEd]

Yes it may not be necessary to control the spark with the MS if I'm not going turbo however, I'm not doing this mod for the power gain. Triple carbs are getting about 10mpg right now and i'm sick and tired of tunning them every weekend. My main goal here is to regain the power i had with the stock FI but to better use the fuel producing a higher mpg. This is the reason I was asking about controling advance with the MS on the stock dizzy. I'm a college student, I don't have alot of money, but i have hands and a vast mechanical knowledge. Modifying the dizzy is not a problem but trying to find a cheap CAS dizzy from a turbo car is just about impossible as they are highly sought after on here. Thank you for the useful advide on what i need to do to the dizzy.

 

-Ed

[z-ya]

Ditch the Webbers and just use the MS to do fuel control. Timing control with the MS will not produce any better fuel economy. Webbers look really impressive, but performance wise they are not compared to modern EFI.

[Nismo280zEd]

I'm having to refrain myself from posting some really nasty comments.

Please read the above post i made and use some common sense.

You are posting in a technical forum. I asked if it could be done, not your personal opinion. If i cared about what others thought, I wouldn't have my Z.

-Ed

[mobythevan]

It shouldn't be too much of a problem to use your NA disributor. Just make sure that you have an amplifier on the input side of megasquirt because the trigger signal from your NA dizzy (variable reluctor) will be a small amplitude. This is where you can use a 4 pin GM HEI module to amplify the signal so megasquirt gets a reliable trigger. I am assuming that your NA dizzy is not a points setup I haven't worked with anything but the turbo dizzies so I am not knowledgable about the NA versions(points vs. electronic)

 

Then as the others said weld up you dizzy so there is no more mechanical advance mechanism. Rotor and shaft are solid. The last piece is to phase the rotor to the cap posts correctly so it doesn't get too far away through the entire advance range. On a turbo dizzy this end of the rotor is physically wider to make this phasing easier to accomplish.

 

Some of this may not make sense right now, but it will as soon as you start through the process.

 

There are some really good posts I have dug up on msefi.com that show with pictures how to get the cap and rotor phased correctly when welding up the mechanical advance. Let me know if you run into problems there, maybe I can find them again.

[Tony D]

Well, Ed, I don't exactly know why you would have to "tune" your Webers every weekend---mine were set up once, and other than adjusting idle screw (which usually went right back where it was anyway) when I did a normal tune-up I didn't screw with them for YEARS.

 

So there is something wrong with your setup, and you're missing it. Fix that before putting another system on it, or you will have some hard road ahead when it comes to smoothing out the MS system. You might get 12mpg on a good day with Webers, BTW, if you have a moderate foot. The trick with them is the emulsion tubes and transition port modifications to get a decent transistion. If you lost power with the Webers, my guess is you are pig rich to begin with.

 

Are you wanting to run the Webers with the MS giving you spark control ONLY, or are you going to go back to EFI, and drive it with MS?

 

Again, your wanting to make nasty comments aside, if you clearly stated what you PLAN on doing with the car, instead of giving peicemeal quips we could probably be MUCH more helpful. You say to "read your posts" but damn, dude!

Your first post says 280Z. COMMON SENSE would say Stock EFI. We are not telepathic here---you said nothing about Webers. That didn't come till the 9th post in the thread.

 

I'm still confused beause you haven't really CLEARLY said ANYTHING...

 

So let's clarify:

What are you DOING, and what are you PLANS---no hidden things here, put it up front so we aren't guessing or making assumptions. What needs to be seriously and clearly addressed...

 

Are you planning on using the EFI going back to the stock or a modified manifold, or the Webers?

 

Are you planning on running IGNITION ONLY--using the MS as a controllable ignition box?

 

If it's the latter, you probably would be cheaper to get a recurved dizzy and have better results than the rather complex path of making a locked down unit to trigger an auxillary spark control box, and driving the igniton that way.

 

I will tell you this, while a programmable ignition will sound good, it's just not really needed on an N/A engine. A recurved dizzy works well, and is the design complement to the Weber Conversion since they don't have vacuum advance. I will agree with the above statement, the programmable ignition is not going to solve your MPG woes.

 

For that, you will need to ditch the webers, and run close to 18:1 AFRs in the two or three lowest MAP bins--with that you will get 30mpg with a 3.9 rearend and an early five speed. (Though to be honest, that is with triple throttle bodies...)

 

But changing the igniton alone? Ain't gonna do nothing appreciable for your mileage.

[z-ya]

Ed,

 

Nothing negative intended, we are just trying to help you. Give us some of the information Tony has requested, and maybe we can.

[2802NR]

This thread is exactly what I have been searching for. I will also be switching from the stock 77 EFI to MS soon and have been re-searching what I need/dont need. I am running a 10.4-1 CR NA motor and am going to MS and a custom Intake manifold in order to utalize my cams powerband (3K to 7K rpms) for track days & time trials. it is also a daily driver. Here are the questions I have:

 

1) Tony, when you say "re-curved distributor" do you mean an aftermarket unit like the mallory or can I re-curve or have someone re-curve my stock unit? (stock 77 dist.)

 

2) I see everyone mentioning the MSD 6A unit. Does the rev limiter on the 6AL cause problems with the MS tach signal? Or are you guys just talking about the 6A family as a whole?? If possible I would like to have a rev limiter which brings me to my next question.

 

3) Do any of the MS versions have rev limiters? I have read over and over the MSEFI info pages and havnt found anything. this is why I want to use the 6AL unit.

 

4) Wich MS version would you guys recomend for an NA setup like mine? I was looking into MS2 but if I dont need/wont gain anything from an adjustable ignition map than I would like to keep things simple. Let me re-phrase, I want to keep it simple but i want a setup that will fill all my needs for years to come. I will be making more modifications but i dont plan on ever putting it under boost.

[z-ya]

I've never used an MS with an MSD, but I would think you can use the tach output of the MSD to drive the MS, and run just fuel control. Choose whatever distrbutor you want based on what advance curve you require. Starting with a NA 280ZX disty is probably a good start if you have one kicking around.

 

Depending on what version of code you run, will determine if it has rev limiting. Your MSD also has rev limiter modules so you can use that too.

 

I would get the MS-I with the version 3.0 PCB. A version 2.2 will also work just fine if you already have one. If not, get v3.0, it is much better in many ways. See http://www.msefi.com for all the details.

[Nismo280zEd]

Yes a 280z is stock fuel injection. Most people on this forum know how my car caught fire a couple years back and I've been running webers ever since. Yeah, I guess if you had the money to do the webers right you wouldn't have a problem, however texas heat and humidity combined with expensive parts have caused me a small nightmare. Yes the webers do run pig rich that is why they only get about 10mpg. Fixing this problem would in no way benefit me with fuel injection. I'm not quite sure where you were going with that one. I have a JSK fuel log, shaved N47 head ported and polished Non egr manifold ported and polished, 240sx TB with sensor, cable conversion. Running stock spec injectors till i get everything running then I might switch to zx turbo injectors. I have a nissan race cam giving me power from 3k on. Fuel lines are converted over to 3/8" SS hard line with AN fittings and flex connectors. Well I think this gives you a good enough picture of what i'm doing. It's a full fuel injection build up preparing me for a turbo later on down the road. This is why I bought the V3 board for MS as well. My question may seem strange and odd but all i simply ask for are answers. I'm going to school for an EE degree and this has been a very fun project thus far. Right now I only plan to run the MS with fuel control, then since i was a previous computer science major, I'm going to re program the code to my liking since i know the language. I'm also going to have it control my cooling fans, possibly even fuel pump. I asked about the distributor out of pure curiousity.

 

The last couple posts were very usefull and I fully understood what they were talking about. Once I get the z running fine with fuel I'm going to play around with ignition control from it. It's only a matter of time before the ignition module goes out on the Z.

 

-Ed

[z-ya]

For some reason I thought you were trying to fix your Weber problem by using an MS to control ignition.

 

So my suggestion would be to get your MS up and running with the stock disty for ignition. Trigger off the "-" terminal of coil with the "Dave Cap" mod (not sure if there is a place holder for the Dave Cap in the V3 board). I've got a couple maps to get you started, one with NA injectors, and one for turbo injectors. My NA 10:1 L28 with a stock cam made 165HP at the wheels with this map.

 

When you are ready to go turbo, and you want ignition control, go with EDIS. In my mind, it is the best way to go. It eliminates the disty, and it uses Ford hardware that is easy to get in junkyards. Myself and BRAPP are in process of doing the EDIS ingition with MS: http://forums.hybridz.org/showthread.php?t=103781

 

I'm supercharging my 240Z Solo I 240Z, and BRAAP is installing it on his NA Solo II 240Z, so we can provide some help. BY the time you are ready for ignition control, we should have all the dos and don'ts worked out.

 

Best Regards,

[speeder]

I have a Megasquirt built and have been lurking in this section for a while. I plan to use a locked- timing MSD VR distributor and have the MS control timing for a conventional distributor/ coil ignition. This is not on an L6 - I'm talking general setup here.

 

Looks to me as if you have a signal from your distributor that is compatible with the Tach input of the Megasquirt (Such as the MSD or the 280Z VR distributor amplified by an HEI module, as in Moby's sticky drawing http://album.hybridz.org/data/500/8239mss_vr_schematic.jpg -with the MSD in plce of the HEI on the FIDLE output), and if the Fidle output can trigger a MSd box, then you're set to use MSnS to control timing and use the MSD to drive the coil.

 

Unless I'm missing something very basic, this discussion got way more technical than needed.

[Metro]

Looks to me as if you have a signal from your distributor that is compatible with the Tach input of the Megasquirt (Such as the MSD or the 280Z VR distributor amplified by an HEI module' date=' as in Moby's sticky drawing http://album.hybridz.org/data/500/8239mss_vr_schematic.jpg -with the MSD in plce of the HEI on the FIDLE output), and if the Fidle output can trigger a MSd box, then you're set to use MSnS to control timing and use the MSD to drive the coil.

 

One note, if you have a v3 board, it has a built in VR conditioner so you don't need a HEI module to amplify the signal. The VR distirbutor can be directly wired to MS. I'm using this setup with my 76's distributor.