Pretty good speed, but whatever prop you're running, it's got way too much pitch, if WOT is only 4800! Max power is at 5350 and
Optimum rpm for a 2010 175 is
5500-5600 with your max load! First make sure motor height is correct (AV plate above green water) and tach is accurate (preferably I-Command digital).
Is that bracket taking on water?! That'll sure make it sit low in the back! What is your min planning speed? What prop are you running now? I have some 4B props you can try. Denny