04 triton 21x set up help

[Lunkerville]

hi there.need help in setting up my triton21x with a 225 evinrude ho. i've tried the 26 and 28 raker and now trying out the 27 trophy plus.i have a 6" jackplate it's set at 6"in. above the transom. only getting up to 68mph and chinewalks. the rpm is at 5300 and wp is at 16psi.i know it can go little faster.need some help!!!