Help! 1996 C4 after rebuild won't idle and stalls when put in gear

[Hawk73ku]

I'm not a mechanic but my father ran a shop that I helped in when I was a kid. This is first major thing I've done in 40 years since.

1996 C4: after rebuild won't idle and stalls when put in gear. (automatic) No errors in OBDII: It's now a 383 w/Lunati cam: Duration 250/256, Lift .437"/.454", LSA/ICL 112/108

I'm at a loss. Any help is appreciated.

Car starts normally without touching gas pedal and pretty instantaneous. When it stalls, I must press gas pedal to floor to start. It does idle but will stall from time to time. Stalls immediately when placed in gear. Can goose fuel pedal up and down enough to keep it moving but obviously doesn't want to stay running.

Things I've done:
Wouldn't start:
Compression test: 190 all cylinders
NOID test good
OHM test injectors good
Spark Test good
no fuel pressure: replaced Pump, Regulator, and Pulsator: now have 45 psi that holds and vehicle starts.

Rough run: no errors in OBDII
triple check plug wires
radiator chemical and pressure test and both good
replace injectors
replace MAF
replace MAP

 

[DonB]

How much vacuum is it pulling?

 

[Hib Halverson]

The level of modification to the engine would require recalibration of the engine computer in order to get the engine to run properly.

Has that been done?

 

[Hawk73ku]

The level of modification to the engine would require recalibration of the engine computer in order to get the engine to run properly.

Has that been done?

I have ordered a tune from Solomon but the engine is misfiring and coughing through the intake. I contacted Cooper Corvette and they said they would replace the Optispark because my symptoms were consistent with a bad optical. I'm waiting on the new part.