MSefi.com read only forum (Jan.15,2018)

Hello all,

I have a 1998 k3500 vortech 7.4 with a 4l80e 4X4. I have been experimenting with and have the resources to build a woodgas generator to run my truck. The only issue I have is I am unable to advance the timing to be able to burn the gas properly as it is a slow burn like alcohol. I don't really want to loose the fuel injection I already have. I can shut down my injectors, to run the gas, and leaving the timing where it is ...but I will lack performance and possibly give my ecm all kinds of codes. I would like this to be a dual fuel setup and to be able to change back to gasoline on the fly....is it possible to set up a ms2 to control..spark...and transmission, a/c and such...and flip a switch....and turn off the megasquirt...and turn on factory ecm?...My other option is swapping out the intake, to a carb, adding an hei distributor, and installing a stand alone controller for the tranny.

Thanks for your input.

MS2 spark control is straightforward enough, but transmission control will require an add-on GPIO board. In principle, this setup should work.

I have a similar truck, 1993 7.4 with 4l80e. I run the transmission, ignition and all other gm stuff off the gm computer and that includes the fuel pump, and 12 volt to the injectors. I have the gm system trigger a msd ignition box which gives a good signal to the MS2. Only the triggering of the injectors is controlled by MS. I don't have a on the fly switch but have a weather pack connector so that I just switch two wires and I am back to having the injectors fired off the gm computer. It has worked well so far and doesn't even throw any codes although you might as yours is OBD2. For you advance problem you might be able to put in retard boxe that the racers use and then bump your static initial up what ever you needed for the woodgas ( say 10 more degrees ) and when you switch back to gas just dial in 10 degrees of retard. Just for interest I am going to install a crank trigger so that I can run my ignition off MS and leave the trigger in the dist hooked up to run the 4l80e.