What should I expect from 450hp?

sorry, not true. There is basically no difference between a 3.23 and 3.55 gear. Very little. Barely noticable
There is a big difference between a 3.58 and 4inch stroker crank. Real big. Very noticable

408/500 lbs-ft 1st gear 2.45 x 3.23 x 500 lbs-ft = 3957 lbs-ft
360/440 lbs-ft 1st gear 2.45 x 3.55 x 440 lbs-ft = 3827 lbs-ft
340/415 lbs-ft 1st gear 2.45 x 3.73 x 415 lbs-ft = 3792 lbs-ft