Good Morning Folks. Need a little advice here.

First off I'll list some specs:

Car: 90 Integra GS Hatchback 5sp
Engine: LS/Vtec B18A bottom end B16A Top end
2001 Integra Type R Cams
Wiseco High Compression Pistons (11.5:1)
Forged Rods
Full MSD Ignition/Coil/Dis Cap
4-2-1 Header
Cold Air Intake
2.5inch Custom exhaust with 2 resonators
B&M Fuel Pressure Regulator & Guage

Problem: Upon hard excelleration and cross over into vtec engine bogs (like missfire) and puffs out black smoke from the exhaust.

Motor has been freshly rebuilt with all new parts + machining etc etc. Here is where the fun begins.

I was running a nitrous setup with all the accessories (bottle heater, msd rpm electronic switch, guage, purge, remote bottle opener). When the nitrous setup was installed I first noticed my problem(see above for description of problem). I thought there was some crazy internal detonation happening inside the engine from the nitrous. Long story short I took out the nitrous yet the problem remained.
Borrowed a Honda Fuel Pressure tester from the local honda dealership to see what was happening to the fuel pressure when the problem occured. Disconnected my B&M Guage, hooked up the Honda one and off I went. Suddenly my car ran like a dream, didn't bog down or anything. Unsure of how the guage itself could be causing the problem I gave back the honda guage, put a banjo bolt (off of another integra) in and got a new fuel pressure guage. Without installing the new guage my problem re-occured! Argh! It is an intermitted problem. I have an autometer oil pressure guage which registers no lack of oil pressure.

Sorry for the long story. Anyone had this happen to them? or something similar. Looking for a cure.

-Rik

P.S. no engine codes thrown ever.