No Low Range Power in 3.8

:banghead: Hi I'm new to the forun. I've got a '95 Stang with a stock 3.8. It has 185,000 miles on the body & 20,000 on engine. I've replaced the O2 sensors, new gas & air filter, fuel regulator, egr vac regulator. timing at 10deg btdc, fuel pressure is 36psi, jumps to 40 psi when running. Car has no power in low rpm range. When it reaches 2000 rpm it tends to have power untill I shift & the rpm's drop back down. It has no codes comming in so I'm at a loss. Please help!