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

Boy ohh boy nothing gets a response like a good 318 question.

For the supposed Rodney Dangerfield of Mopar engines, they seem to garner a ton of respect.

Look, if you wanna make some power you have to address the culprits holding it back. They're the same with every gasoline engine. You need enough flow to get to a certain power number, you need compression and/or displacement to build torque, and other bits matched to your intention, like valvetrain/intakes/exhaust.

There's no magic button (well , nitrous not withstanding) to get the combo where you want it. In my opinion you're gonna have to do some real work.

My 2c, find a relatively low mileage junkyard 5.2/5.9 out of any of a zillion trucks and swap it in. Buy a cheap intake and headers and you'll get to 300 hp or thereabouts. Throw a cam and a converter at it and things start getting serious.