4 blade prop for 23' ?
 

I have a '76 23ft. Seacraft with a 2002 Yamaha 250 on it, center console. I currently am running with a 3-bladed SS prop, was wondering if anyone was running a 4-blade, what the diameter and pitch was, and if they noticed improved performance? I'm burning around 14 gph at 4400rpm, 22kts. currently. Thanks guys!