if finances are a challenge then just rebuild the 390 with some good compression, good intake and carb and a healthy cam that matches the rest of your combo with some opened up heads and your 390 can make over 400hp. if you want serious hp and have some money to throw at it i would go 460 versus strokin the 390 unless you wana stay with FE and theres nothin wrong with that. the reason i say go 460 if you have money and are serious is baecause you can spend 1500 strokin your 390 to 445 and have 450-500hp or you can spend 1500 strokin a 460 tp 545 and have a calm cool 550 to 600hp depending on the heads you use. ported iron heads on a 545 can get 600hp with ease. like wilker said, depends on what you want. a nice healthy 390 is lots fun