* Engine build specifics: The type of heads, camshaft, intake manifold, carburetor/fuel injection system, compression ratio, and internal components (pistons, connecting rods, etc.) all drastically affect horsepower.
* Tuning: Proper tuning of the fuel and ignition systems is crucial for optimal power.
* Engine condition: A well-maintained engine will produce more horsepower than one that's worn or poorly maintained.
A 388 stroker is a modified engine, typically starting with a smaller displacement engine and increasing its size through modifications to the crankshaft stroke. A well-built 388 stroker engine *could* produce anywhere from 350 to over 600 horsepower or even more, depending on the factors listed above. It's a very broad range.
