help with a 383 cheby

Did you buy it new? Is it an automatic? I got a set of injectors from a 'vette, and changed the chip because my '87 was like that. Helped a little. The real improvement came when I swapped out what I suspect was probably the wrong torque converter. I took one from a TH-350 and put it in my 400. Hit the throttle and all my tool boxes went flying everywhere. However, it is a truck and with the 3.06 or 3.09 gears, I can't remember which, it still gets crappy mileage, but I can at least pull out into traffic without being killed.