It's really hard to model a vacuum leak: With a fixed leak area, the leak volume is proportional to the pressure across it, the humidity, and the barometric pressure; and it's nonlinear.
You don't know what the vacuum level is, so you have to guess, and the barometric pressure/humidity relationship is based on that guess, and you have to model a fueling response based on those guesses; so that makes your mix at any given time a third-order guess relationship, and that will never fucking work.
Enough time and effort could model the response for a given leak for a drag run, changing absolutely nothing on the car, but it would take months to tweak. And fail if the weather wasn't close to the same.
And if the leak area changes any, every assumption you made is now wrong.
Red '96 Cougar XR-7 240k mi. '02 4R70W, PST DS : '03 PI engine, 04 maf, 24lb injectors, 2.5" exhaust, '02 4r70w + Jmod, DirtyD0g TC + cooler + 3/8" lines, 255 walbro fp. Alpine system.
Black '96 Cougar XR-7 (Lazarus) 210k mi PI Intake, '02 4R70W, Jmod, PST DS, GrogTune, Konis, Mark LCA+Poly, racecougar Custom Engine Chain, and JL and racecougar Bracing.
Black '97 Tbird Limited Edition, '02 4R70W, 255 walbro, PST DS, PBR Brakes&SS lines, Toicko Blues & Springs, GrogTune.
I'm not Human enough to be human; but I'm trying to fit in, and I'm learning to fake it.
"Never said Hibbity..." - Brian Williams