oil pressure dopping on 16v...

[190evol1]

in the 8-9 years i've owned my 16v, i've never seen my oil pressure drop below 3 bar. a couple of years ago, i needed a rebuild and opted for the 2.6 stroker kit with sport cams (276). so, i've posted questions on its tuneability, rough idle, and performance on this forum. so now, my mechanic got a new head tech who fixed my hard starting and rough idle - car runs like a dream (or the way it should have after the stroker to begin with).

however, i immediately noticed my oil pressure dropping after the engine is warmed up. on highway cruising speeds, it drops to about 2 bar. in traffic and idling, i see it closer to 1 bar. my mechanic said it needed an oil change (i use mobil 1), so i changed it > no major difference. a week later, he changed it to non-sysnthetic and charged me a pretty penny. no big deal, atleast the pressure is back up.

so, a month later: it's dropping again! is it really the oil viscosity? some people tell me problems with the oil pump or even the sump... at this point, HELPPPPPPPPp!