Port injected low deck project.

Generally plenum volume matches total cylinder volume in high horsepower applications. When we build a plenum for say a 2.0 liter engine we match the intake plenum to 2.0 liters. This way the plenum can hold enough air all at once to fill every cylinder completely. Shape is important too. If the plenum was just a big rectangle when the air passed over the throttle body it would be launched to the top of the plenum, hit the plenum roof, and be forced towards the rearward most runners, not completely distributing the air. Tapering the plenum towards the rear and playing with different shapes at the rear should slow down incoming air velocity so it moves into the fronts as well.

Im a big fan of the Megasquirt system and use it on 90% of the installs we do. For stand alone engine manangement it feels like a science project at first, but its possibilities are almost unlimited.

Bosch, Denso, JECS, Siemens are all good injectors.