300 HP out of a 318, is it possible with bolt ons?

suppose I should qualify that as at the flywheel. 300 HP at the rear wheels would be more like 360 gross at the flywheel, which might still be possible with a stock short block, headers, something like an RPM air gap, magnum heads, and a cam in the [email protected] range. this is a good, but older article: https://www.motortrend.com/how-to/mopp-0409-318-engine-build/

personally, I'd just start with an '85-up roller or magnum engine, and look at doing a reground roller cam. it allows for more aggressive ramps, and longer .200" duration for the same amount of .050 duration, getting more air in while also giving better street manners and low end...