* Lobe Separation Angle (LSA): 350 cams are often designed for a larger displacement engine and might have a wider LSA than optimal for a 305. A wider LSA can lead to less low-end torque in the smaller engine.
* Valve Timing: The duration and lift of a 350 cam might be too aggressive for a 305 with stock heads and other components. This could result in poor low-end power, reduced fuel economy, and potential valve-to-piston interference (especially if the cam has a high lift).
* Overlap: Increased valve overlap (when both intake and exhaust valves are open simultaneously) from a larger cam can negatively affect the 305's performance, potentially leading to reversion (exhaust gases flowing back into the intake).
* Spring Pressure: The stock valve springs in a 305 might not be strong enough to reliably control the higher lift of a 350 cam, leading to valve float at higher RPMs. This can cause serious engine damage.
In short, while it might *fit*, using a 350 cam in a 305 without other supporting modifications is likely to result in a less-than-optimal, and potentially damaging, outcome. To make it work effectively, you'd likely need to consider upgrading the valve springs, possibly the pushrods, and potentially the heads themselves for better flow. Choosing a camshaft specifically designed for a 305 would be a much better approach.
