mobythevan

I'm not even sure it helps with huge injectors. I have been researching that because I have 150# injectors on my 5.3. With injectors that big it doesn't really matter that you give it a fine resolution pulse, it can only open and close so fast which means you get a lot of fuel and you can't control it. It would provide the ability to time the injection pulse with valve events which may help with huge injectors, but otherwise it doesn't seem worth it. I think MS3 is for the crowd that is bored with MS2 and needs something to tweak. Like you say, it will work well for economy so that may be the bigger crowd for MS3.

I can understand where you are coming from. The only thing I want to add is that triggering with a VR signal is the single toughest thing to do with megasquirt installs. I avoid it at all costs, but I'm a whiner BTW, your coil will have a marking that shows which post is positive and negative. Run your coil negative trigger wire all the way to the coil post if your not sure which wire out of the harness to use.

In order to have MS control the spark with a VR type dizzy you will need to weld/lock the dizzy if it has a mechanical advance mechanism. There are threads that talk about ways to do this. Once MS controls the spark it will take care of all the advance/retard.

If it was me I would just put an 83 zxt dizzy on there and use the optical CAS from it to trigger megasquirt and then run fuel and spark. That setup has been proven many times over. I wouldn't waste the time to mess with a VR dizzy setup just to run fuel only. (my two cents)

Nothing connected to pin 36 is correct for a fuel only install. Pin 24 to coil negative is correct. I don't understand what you are saying about nothing connected to the positive side. Do you mean the coil positive is not connected to anything?

You should look at the wiring diagram for your car and decide which wire meets these conditions to power megasquirt. I don't know off hand. You will want to become familiar with reading your wiring diagram anyway or your megasquirt install will become very tough to deal with.

Megasquirt needs power during cranking and running. This is a very common mistake to only have power running and lose it during cranking, fix that first. Make sure megatune or tuner studio is communicating with megasquirt before cranking over the engine. See that temp gauges and other stuff are working, then see if you still show no rpm.

And always put a copy of the shipping info inside the crate/box. The guy that shipped me a transmission only put a label on the outside which quickly tore off and my crate got routed to over goods (lost in space).

That would work if you have stock dropping resistors. I didn't think z cars had them, but maybe I am thinking of the earlier years.

Looks to me like you have the 1k resistor in correctly. Now you should put a touch screen in place of the glove box door so the passenger can tune anytime they feel like it.

I used dropping resistor packs from an eclipse on my LSx V8. I also use a relay board, it has 12 volt switched for the injector power. Just the way I did it, not saying it is a good way.

I know its old school, but I like Tony and his simple ascii diagram: Tony D. ascii diagram for wiring your injectors: 12V+ ----- Resistor Pack ----- Inj1+ Inj1(-)-----\ 12V+ ----- Resistor Pack ----- Inj2+ Inj2(-)------SPLICE ----- INJ1(Gnd for Injectors thru MS) 12V+ ----- Resistor Pack ----- Inj3+ Inj3(-)-----/ 12V+ ----- Resistor Pack ----- Inj4+ Inj4(-)-----\ 12V+ ----- Resistor Pack ----- Inj5+ Inj5(-)------SPLICE ----- INJ2(Gnd for Injectors thru MS) 12V+ ----- Resistor Pack ----- Inj6+ Inj6(-)-----/

I see the winner will be announced on March 15th. Do you work at this barber shop? Just curious what their story is. For all of us from a different part of the country you should give us some background.

Now you know why I live here:

Since I am still low on funds I am thinking of putting a stock converter on the powerglide and driving the car non-turbo this summer. Its a 5.3 with an LS6 cam so it gets around ok without boost. Guess I better put a muffler on it too

Without knowing your car, engine, current ingition setup and any other details it is hard for us to help. If you have a distributor and single coil, then you run a wire from the coil negative terminal to the megasquirt input. EDIT: I meant it is hard to supply a specific photo of the wiring when we don't know if you have a 240z and stock engine or 280zx and stock engine for example.

Out of curiosity, what is megasquirt showing for injector duty cycle if you log it? If your required fuel settings are reasonably close for the injector size you are running then the duty cycle should be reasonably accurate. If it shows above 85% under load then it is another feedback that your injectors are too small.

At this point I would have to put a scope on it to see that the stim is really producing an rpm signal and then if the signal makes it up through the opto isolator circuit. I don't know what else to tell you at this point. Can you try your stim board on a different megasquirt to make sure it sends and rpm signal? Anyone local to you that can help with that?

Was the main board pre-built or did you assemble it? Maybe the opto IC is in backwards?

Yes, use the 22v zener. I am not guessing about the post above when I said the main board is the same for either MS2 or MS3(for the opto circuit, maybe not for other circuits on the mainboard). I looked at the circuit and the zener diode has nothing to do with using an MS2 or MS3 processor.

I don't believe the instructions for this part should differ whether its MS2 or MS3. This is the same circuit on the mainboard in either case. It only controls the opto isolator input side. The opto output side interfaces with the MS2 or MS3 processor. I think either zener will work in either case.

Also, you need "tachselect" jumpered to "optoin" "optoout" jumpered to "tsel" XG1 jumpered to XG2

The instructions from msefi.com are: So it looks like they want a 24v zener. If DIY provides a 22v zener I would use it.

Is your base board set up to get the trigger input to the processor? I assume your using a v3.0 pcb, it has a couple jumpers that need to be set up to get the tach trigger working.

Oh, now it hits me, you are talking about people using the EDIS module. At first I was having a hard time understanding why EDIS people cannot use spark cut but I forgot that some people use the EDIS module and the only thing that megasquirt tells the module is what timing angle. I have two wasted spark engines but I use the megasquirt wheel decoder and no external modules. Sorry for the sidetrack, I just didn't understand why you couldn't use spark cut at first.