Can you put heads off of a 396 on 350?

It is possible to put the heads from a 396 engine onto a 350 engine, however, some modifications will be necessary to make this work. The 396 heads have a larger combustion chamber than the 350 heads, so the compression ratio will need to be adjusted to compensate for this. This can be done by milling the heads, using thinner head gaskets, or both. Additionally, the 396 heads may have a different valve arrangement than the 350 heads, so the valvetrain may also need to be modified. It is important to research and plan carefully before attempting this modification to ensure that the engine will function properly.