I’ve been in lurk mode for a while now, trying to learn the basics.

I’d like to make sure I understand the way GM EFI systems works, before I start spending $$ on parts.

Is it correct that a MAP TPI system fires the injectors once per engine revolution, or is it once every other revolution?

Are all the injectors fired at the same time or does one bank fire and the other bank fires later?

On a TBI system, is each injector fired twice per revolution, and with two injectors, the system ends up firing two injectors, twice per revolution, giving four squirts of fuel per crank revolution?

Both TPI & TBI injectors are high impedance?

GM ECMs use 4/1 injector drivers for both TPI & TBI systems?

 

here read this, bye the time you get through youll have the idea



http://www.diy-efi.org/gmecm/

http://www.fuelinjection.com/portinj.html

http://www.customefis.com/

http://www.chevyhiperformance.com/ed....jsp?id=49738& viewtype=text

http://www.chevyhiperformance.com/ed....jsp?id=49279& viewtype=text

http://www.chevyhiperformance.com/ed...e.jsp?id=18459