The term "bored out" refers to increasing the cylinder bore diameter of an engine. Whether a specific 350 engine has been bored out depends entirely on that individual engine. Many 350 cubic inch engines (a common small-block Chevrolet V8) are *not* bored out and remain at their original factory specifications. However, others have been modified by their owners or builders to increase displacement and power by increasing the bore size.
So, the answer is: Some 350 engines are bored out, and some are not. You need more information about the specific engine in question.
