I'm going to crank the car tonight but I want to make sure i have my baseline settings correct.



Installing MS II V3.0 on a '73 2.0 (4cyl, port injection, 4 injectors, low impedence injectors, speed density). My required fuel came out to be around 13. (122 cubic inch, 4 inj, 24 lbs/hr) Stock 2.0 injectors, plenum, runners.

Do I want 2 or 4 Injections per cycle?

Injections per Engine Cycle is set the number of squirts you want per engine cycle. You want this to be set so that your idle pulse width is no less than 2.0 ms, if possible, and your Req_Fuel is less than 15-18 milliseconds, but more than 6 milliseconds. These values allow proper tuning of the idle mixture while maintaining the ability to apply enrichments (acceleration, warm-up, etc.) under full throttle. This is the total injector events that you wish to occur for every engine cycle (360 degrees for two stroke engines and 720° for four strokes.


What about injector staging? Alternating or Simultaneous? (alternating is my guess)
Even fire or odd fire? (i say even fire according to MS II documentation)

Do I setup my injector banks as follows?

INJ1 - Cyl 1, 3
INJ2 - Cyl 2, 4

This is the firing order of the dizzy:

i believe the dizzy numbering is incorrect but the sequence is right.

I plugged into the calculator here:
http://www.megasquirt.info/v22manual/mfuel.htm
Disp 122 cubic inch, 4 cyl, 4 inj, 4 squirts, 24 lbs/hr, alternating, gas.

That gave me Req Fuel of 13.3ms and downloaded req fuel of 6.7. This satisfies the required fuel range above of 6-15ms. So are these settings acceptable?

Thanks

Yarin

I use 4 per cycle, alternating. Check the number of cylinders you have. It should be 4 and 4 injectors.

Dave

ok, I am running the following...


required fuel 11.6 (36#/hr injectors)

2 injections/cycle
alternating even fire, port injection

sounds like you are close...just try it. you should be able to tell if it is lean or rich.

if it backfires, then its lean.

Ok so i'm on the right track, i'll see how it goes and check the WB02 assuming its setup properly.

The screen capture i posted is the default settings from the MS site. i'm at work and wanted to post a sample.

Mine, 2056cc with 1.7 injectors

whoah.. pretty large range of configuration that work for different people.

what about the injectors? do i have the two banks hooked up properly?

Yep, Djet is ol school but ya just turn the little screw to tune it, pretty basic and KISS.

But I do hear the call of laptop tuneable calling me!! Maybe for Blairs black car.

Ahhh crap... go figure, i missed something:

However, it is important to understand that there are differences between the ignition input signal needed for MegaSquirt-II versus MegaSquirt:

MegaSquirt needed one signal per ignition event, but the timing was not critical.
MegaSquirt-II needs one signal per ignition event, but this signal MUST occur at the advance offset with respect to TDC.
So you CANNOT use the negative side of the coil to trigger MegaSquirt-II because the coil already has timing advance built in, and using it for a timing signal will screw up the total advance severely. You must use the appropriate distributor or crank wheel for your ignition module.

Argh... there goes my plan to start things up tonight. I was planning on triggering off the (-) side of the coil on a centrifugal advance unlocked stock dizzy until the fuel is dialed in. Looks like i'll have to run spark off the bat. Not a real concern, but I don't have a timing light here in connecticut. I'll have to pick one up at home this weekend. Unless I can buy and return one from autozone... hehe

ummmmmm....

I am using the negative side of the coil...no problems.

I am using the mechanical advance for the spark advance.

if you aren't going EDI, it work ok with the stock dizzy....

The tach signal for a fuel only setup shouldn't care about how it's timed, even with MS2.

The tach signal only needs to be synced with the crank when MSII is controling the spark output. If you are doing fuel only it does not matter because the injection squirts don't have to be timed with any particular valve event.