plane

Hey guys I've posted on a couple sites and am still looking for help, I just bought my first bass boat and I'm having a problem with it getting on plane. It's a 1994 Nitro 170 DC Rick Clunn Edition with 115 hp Evinrude, I got a hell of a deal on it so I felt like it was time to pull the trigger...

I just bought this boat a little over a month ago and have taken it out 4 times or so. Its not my first boat.. so I'm experienced with getting boats on plane.. but damn this boat is a tuff one! this is 20' 2" and paired with the Mercury 225 Dfi (3.0l).. Currently I'm replacing spark plugs...