what's the main difference between and 350 tbi and a 305 tbi? is it just the injectors? or is it more? also, would the ecm chip out of a 350 work in the 305? kinda like the hyperchips stuff? i don't know **** about that stuff.

Check out the new to TBI sticky above. It goes into detail about the LO3 (305) and LO5 (350) TBI motors. Besides the extra cubes the LO5 came in many different configurations and ranges from 190hp to 220 (IIRC). Depending on the GM platform some were roller motors and others weren't. Likewise, specific markets (cop cars, trucks, full size cars) for the vehicles equipped with LO5's had different injectors (yet had the same 1 11/16" TBI unit as the 305's). To my knowledge they all had swirl port heads with 64cc chambers (193 casting).

The chips found in B-bodys are compatible with the ECM in your f-bod but it is not a "performance" upgrade if added. It has pre-set parameters to control the LO5 that it was paired with.

Take some time to read the afore mentioned stickies and that should help clear things up for you.