some wirring info

[mopar3.0]

does any one know how the older 3.0 bacth fires its injectors?
were there 3 wires togetherm or in sets of 2

im trying to figure how to wire em for my mega squirt
i was thinking 123 channel 1 456 channel 2

[mwinkle353]

three sets. They fire in pairs. 1-2, 3-4, 5-6


The way you want to run them is fine. That's how my Nissan fires it's injectors.

[mopar3.0]

hay m90 daytona how do you fire yours?

[87turbodance]

I would just group the 3 injectors in each bank together and run 2 squirts alternating. Or, you can just run all 6 injectors on channel 1 and save channel 2 for something like water injection using some FFV injectors in addition to your fuel injectors. Using channel two to run a couple FFV injectors allows you to have a VE table for your water injection which can be very handy if you like that sort of thing

[mopar3.0]

i am gona run meth injection, but woudnet firing em all at once dump a lot of un needed fule?

[87turbodance]

Firing all 6 injectors at once will make no noticeable different over firing them in banks. A lot of MS users fire all injectors at once then use the other injector table to run meth injection. Batch injection is mostly used to avoid a fuel pressure drop in the rail by having a number of smaller injection events as opposed to one big injection event every engine revolution. Any unused fuel from and injection event just stays suspended in the intake port waiting for the intake valve to open. No extra or unneeded will be added or wasted. Even sequential injection is only useful at idle and cruise. Once the engine turned at a decent rpm there is no difference between batch and sequential fuel injection because the fuel injectors simply aren't fast enough to open and close every time the intake valve opens and closes. There's some interesting info on this subject in the fuel section of the Megasquirt Megamanual. I recommend reading it

How much meth is dumped all depends on what values you fill in the VE table for the meth injection channel. It can be as much or a little as you like and it would be all easily programmed in a table of boost vs RPM

[DustyR/T]

doesn't firing batch fire or all at once hurt the combustibility because atomization is not as good?

My logic is this. Running at low to mid range RPM and firing all at once is not so good because when the injector sprays the back of the valve say for instance, intake valve 1 is open when cyl 6 and the others are being injected. Fuel may only remain on the valve for a few thousandths of a second, but atomization has gone to crap now. The fuel still gets into the cyldiner but not as consistantly because now some will remain on the valve-though menial amounts, relatively less efficient than the cylinder pulling the fuel in and being directed by the air it pulls around the valve. In both cases, some remains on the valve but with SMPI, it is more efficient.

Just my logic.

[87turbodance]

SEFI will give better idle and cruise economy and emissions but will not make any difference in the power output of an engine. At the present time MS is not capable of SEFI or even timing its batch injection to match the cam timing. Even if your run MS in batches firing two separate banks there is no reason to believe that MS fill be firing at an open intake valve. MS makes no reference to cam position when firing the injectors - it just fires the injectors at a regular interval based on it's tach signal. Once you get into high fuel demands the time required for the injector to stay open is longer then the valve is open anyway.

Bottom line; whether you run MS in two banks or run MS firing injectors all at once there is no guarantee that the batch injection will be firing at an open intake valve so why not save the extra channel for something else? Even if you setup MS with a second trigger using a CAM sensor MS still wont take this information into account when calculating injector pulse timing. These are things that will be implemented in future versions of MS