Got my 87 Caballero with a 305. It failed emissions with visible smoke, took it to the shop and it's run worse ever since. I could've sworn id idled previously at about 1300RPM's but now it's not even half that. What does your 305 idle at? And how would I fix this?

With the engine at operating temperature, no choke, no fast idle solenoid, the curb idle should be 600 RPM.