223 formula

i am new to oso. first off i would like to say hello to everyone. with that being said, i have a 1989 223 formula. i bought the boat with a 454, bravo1 setup. it already has a 2 inch shorty with a nosecone. nosecone is from what i understand pointless unless i can get the boat over 80. probably not going to happen...... anyway, i just swopped in a mercury racing 500 efi. i was wondering what prop i should start out with in my testing. i am getting everything together in the meanwhile for a external assist before i do put a prop on the boat that will make the engine accually break a sweat... the prop is constantly out of the water being it is only 22' and the 2" shorty dosent help any. right now it has a 22" bravo 4 blade. the boat will do 67mph now with the 22 at 5200 on the limiter. if i am cruising at 45mph, and stab the throttle to wot, the engine litterally sounds as if it is free revving and snaps your neck as it accelerates. i was wondering if any of you pros had any advise for me. also, i do have access to an m-1 procharger system for the 500. is it worth putting it on the 500? a friend has the setup on his checkmate and he has had no issues. will my boat handle anything above 80 if i run the charger or will i be close to exceeding the hulls limits in the mid 70's. thanks.