sr20det idles fine, wont drive!

[b145279]

I have an s13 blacktop, all stock including smic. Since install (approx 2 mos ago), starts right up and revs great in neutral. As soon as I put in 1st or reverse and release the clutch, the rpms drop and it bucks/stalls and the gas pedal becomes irelevant to the rpms drop. I have even tried to let out the clutch at up to 3000 rpm and it does not change the outcome. The engine still drops to roughly 500 rpm it dies. I started with all stock items and have systematically replaced with NEW:
AFPR, Fuel Pump, Fuel filters (more than once)
Boost controller, vac lines (vac gauge says vac at 15 @ idle)
temp control sensor, knock sensor
master and slave clutch cylinders and removed damper
brake booster/master.
Timing is 17 btdc
TPS is .43v closed.
FPressure is 40psi w/vacuum
Compr. is 120 across all cylinders
NGK 6's gapped .30
coils are within spec of 1ohm
injectors are within spec of 11.4ohm

I have checked extensively for vacuum leaks, exhaust leaks/obstructions and fuel leaks to no avail.
I am all out of ideas on the problem.
THE QUESTIONS:
Am I overlooking something simple?What?
Could the problem be related to the clutch/trans engagement? It shifts fine, no grind no noise except TOB (I reused the clutch as it looked to be in good condition, throw out bearing is bad though (rattles).
Thank you in advance.