Alright. So, here is my current situation. A buddy of mine has a 350 block from an 89 GTA. It does not have heads, and is close to stock. It has an upgraded cam and some other small things. Anyway, I know that my 305 heads and intake will fit on the block. My question is, how badly will it affect performance until I get new heads? Also, how bad will performance be until I get new injectors and a computer? Will it run worse, the same, or a little better than the 305? Any help is greatly appreciated.