Ok then what is the recipe for a 425-450 horse streetable 340

Well my 340 has 398 hp 413 tq with a basic stock 1970 rebuild ,10.5 mahle forged , pistons , mild porting on the heads with mild hyd cam . Car is a blast on the street , smoke the tires easily , starts first turn of the key . So reliable my wife can drive it . 450 hp would be easy to reach with a stronger cam and a bit more head work .