I have a 2004 alumacraft magnum 165 cs with a 2005 90hp etc.
It goes exactly 41.1 mph in 53 degree temp water running at 5200 rpms with a michigan ballistic ss 3 blade prop 13 7/8 x 17.
Average speed is around 38.8 with full load, 2 230lb guys, full tank gas, full livewell and I have 3 group 29 batteries for a minn kota trolling motor up front of the dash 2 optimas in back for electronics/starting motor.
I am guessing my setup is heavier than yours and my bow lift is extreme. 1/2 trim (on the guage) is wot throttle, trim up on the motor up from that and the bow wants to porpoise.
From the stock 14 x 17 x 3 aluminum prop to SS, I got exactly 3mph more top end. Holeshot on either prop was instant (you actually feel your back press against the seat).
I have 4 extra props, all of which are 19 pitch and above and in each case performance suffered quite a bit.
Hydrofoil will not help, only with holeshot as the hydrofoil runs out of the water at wot.
Are you running SS (stainless steel?)