Hello, I'm putting a 350 into my 86 Camaro which has a 305 at the moment, and I'm wondering if I need a new computer or if I can just add a new chip into the old one. Thanks

 

Just do the swap, I didn't change anything on mine

 

are you running tbi or tpi? im not sure about the tbi, but there are significant differences between the 305 and 350 that can cause issues and poor performance. the 350 has a different fuel map, and requires 22 lb/hr injectors. the 305 uses 19 lb/hr. the knock sensor is also different. at the bare minimum, get the chip, injectors, and knock sensor for the 350. if you have any performance mods done like headers, lower temp thermostat, etc. visit www.pcmforless.com and get a custom tune. its a bit more expensive than finding a used chip, but will get you more power. as for tbi, im not sure if the physical unit is any different, but the injectors are. you can source them new or used