KA24DE with megasquirts Q?

[AK-Z]

As some of you guys know I am trying to do a KA24DE swap into my 280z (frankly for the hell of it so don't argue). The engine is from a 95 S14 I believe with no ECU.

 

Ok, my situation with MS: Since I have a the S14 model of the engine, the distributor is ECCS (ecu) controled much like the 280zxt dizzy setup. Does anyone know if there are people running MS on there 240sx's using this ditributor? I can't seem to find anyone using this setup. I've searched the KA-t.org boards and the MS forums and can't find a direct answer.

 

BTW, for now I just want to have everything pretty much stock. Then when I have everything working, I'll start fiddling around with the damn thing.

[mobythevan]

If the dizzy has an optical wheel in it like the 280zxt and one of the decoder rings has 4 holes then it will definitely work, don't worry if no one else admits to using it. Just pop it open and verify the decoder wheel. Or post pictures of the inside. That will give you the trigger for megasquirt and work OK with spark output since it was already made for ECU control (locked advance).

[AK-Z]

I've already checked and yes it does have the optical wheel trigger and has 4 decoder holes. What I'm really asking is how would I wire it up? It has 2 connections, one is a 6x1 pin connection that I assume is for the optical, and a 2x1 pin connector that I assume is for the ignitor/coil (doesn't use coil but just for refference). Oh and there is another connection that is a single pin for the condensor but thats not important.

 

Thats what I'm really asking, because no one seems to have it setup like that.

[AK-Z]

I figured out what the pin out is I posted this on KA-t.org

 

I finally figured out what each of the pins are for!!!!

 

In the manual it says that the power transistor and coil are internal (part of the reason why I was so confused). Well here is the pin out

 

(6x1 pin connection) 1-2-3-4-5-6

1.Goes to pin one on the ECU to pin 1 and the lead wire is white.

2.Goes to ground and is black

3.Goes to ECU pin 40 and 44 and I belive it is dioded to 44 with it eing positive, it is white

4.Goes to the ECU pin 41 and 45, it is black

5. goes to the ECU pin 56 and 61 with pin 5 on the dizzy dioded with pin 5 being positive, wires are black white

6.Goes to ground, wires are black

 

as fo the 2x1 connector 1-2

1.Goes to the resistor with a light green/black wire and from the resistor to the ECU using a yellow/red wire to pin 2

2. Goes from ignition somewhere using a black/red wireand is dioded

 

So the on the 6 pin the first 2 pins are for the transistor (pin 1 being the signal), the other 4 are for the "Cam position sensor", which I assume I can use as a CAS since it pretty much the same as the zxt dizzy.

 

So now I can figure out how to use MSnS with since the 280zxt version is much similar to this which I am much more familar with. Yeah less parts to buy =))

[AK-Z]

Well here's a schem of what I'm dealing with and a compareo of the setup with the zxt dizzy setup.

 

95 240sx dizzy/ignition out of the manual

 

And then there is the setup thats for the 280zxt 83 dizzy setup that was posted here on one of the stickies.

 

 

 

Can someone help me figure out how I'm suppose to wire this to have it work?

[AK-Z]

Ok I just about have everything figured out.

 

I only have one question and its related to the ZXT dizzy setup. Looking at the diagram the CAS signal that MSnS gets is from the green/black wire, is that for the 1 degree signal or the (remember this is reffering to the L6 engine) 6 hole decoder.

 

In the 240sx manual its called the 180 degree signal (4 cylindar, but shouldn't it be called a 90 degree signal instead? oh well) and the 1 degree signal.

 

Oh another quick question. the transistor, I assume is for ballast so would I just leave the 2 leads to it just disconnected and run the coil with a straight 12v?

[olie05]

remember that 90* of distributor rotation is really 180* of crank rotation.

[AK-Z]

Oh yeah, Duh. :burnout:Well I still need my question answered.

Which source do I use for MS trigger? the 180* signal or the 1* signal?

[mobythevan]

Source MSnS with the 4 slot trigger, the green black wire from the 280zxt dizzy is from the 6 slot wheel, not the umpteen slot wheel . So you want to use the wire from the 4 slot wheel output on the KA24 dizzy. It was easy to tell if you got the wrong one because your cranking rpm in megatune will be crazy high if you have the 1 degree output.

[AK-Z]

Thanks that helps alot. Now about the transistor. I assume you dont wire it up because I dont see a ballast on the zxt setup. correct?

[mobythevan]

I may be missing your question, are you asking about the transistor that fires the coil?

 

If you have a version2.2 board use the transistor on the car to fire the coil, or a GM HEI module (transistor). I just hooked up my Talon 4G63 and I used the stock Talon tranistor to fire the coil (actually two transistors and 2 coils, distributorless).

 

If you have a version 3 board you can fire the coil directly from megasquirt and not use the transistor on the car, because version 3 has the built in VB921 transistor.

[mobythevan]

Also keep in mind that if you use an external transistor it will cause an inversion of the SPARK signal, so pay attention to whether or not you need to select "invert spark output" in MSnS.

[AK-Z]

I may be missing your question, are you asking about the transistor that fires the coil?

 

If you look at the first schematic, you can see the transistor. its an internal component in the dizzy. So if I use a GM HEI modual, then I wouldn't use it, correct?

 

I'm sure I can figure a way to use it but I'm already confused enough and am going off of the zxt instructions to try to figure everything out.

[mobythevan]

Yes use the transistor in the dizzy if possible, cleaner setup. That is the transistor to fire the coil.

[AK-Z]

Ok. Then how would I wire it up with the transistor? Do I even need a GM HEI modual then? From what I can figure out, this is the way to set it up with out the transistor.

 

Look at the first diagram to see out its wired

 

So the pin out is:

1. lead to the transistor, I am guessing that its the signal lead

2. lead to the transistor and goes to ground

3. 1*signal, not used

4. 180* signal,

5. 12v source

6. ground

 

Coil:

7. 12v to coil

8. Negative to coil

Coil is internally connected to rotor.

[mobythevan]

If I read your schematic correctly you have version 3.0 board for Megasquirt?? If that is true then you don't use GM module or transistor in dizzy becuase it is already on your board? Just want to make sure. Otherwise if you have version 2.2 megasquirt board you are on the right track with the GM module.

[AK-Z]

I haven't ordered a MS setup yet. Well I did but they were back ordered so I decided to cancel because I ran into this little issue and wouldn't want to buy, then come to find out that it only work with more parts.

 

So on the v3.0 board, I would only need to connect the positive to the FIDLE with a wire with a 1k resistor going to a 5V source and the negative to ground, as far as coil is concerned. Correct?

 

If I use a v2.2 board, This setup would look like it would work ?(lets face it, we're all just guessing here, lol) What about trying to use the transistor like you mentioned?

 

Maybe if I new how the GM HEI worked, I could then probably find a way to make MS work with the transistor.

[mobythevan]

On a v3 board pin 36 on the DB37 connector is for coil control. This how a coil connects to v3 board, nevermind the VR inputs:

 

 

Coil + always goes to constant 12 volt. Coil - goes to your tranistor which temporarily connects coil - to ground to fire the coil.

 

If you want to use the tranistor in the dizzy, then connect pin 2 to ground (transistor emitter), connect FIDLE to pin 1 with pullup resistor (transistor base), and the coil - is already connected to the transistor collector according to that schematic. Connect coil + (pin 7) to 12 volts on during cranking and running. Then stock resistor and ignition module in the schematic would be removed.

 

That should give you the correct way on all three setups, v2.2 with GM HEI, V3 with VB921, v2.2 with stock dizzy transistor.

 

Now get that thing ordered.

[AK-Z]

So where do you suggest in buying a kit from? Firmware?

 

Well from what you said, this is how I thikn it would be wired. is this right? And on the v3.0 wire up, in the blue, is that right ? Shouldn't the resistor be wired in with the 180* to the relay board and not connected to 12v with a 1 k resistor?

 

v2.2

 

v3.0

[mobythevan]

I still think you want the 1K resistor to pullup on the FIDLE to the base of the transistor like it does to the "G" connection of the GM hei module(not inline lik you show it).

 

Yes, if pin 4 (180 degree) is the 4 slot output then everything else looks correct. I personally like to buy the megasquirt v2.2 from Jerry at DIYautotune unassembled for $134. That price rocks

 

Run either 024s13 code or the newly released stable code 029q

 

Better to stick with 024s13 because there are less options and less confusion.