First, go to www.HowToWakeSurf.com
The site has a lot of text but it is important information. Next, ballast your boat adequately. In our 2001 Tige 20i, we use about 2000 lbs of ballast. To see a picture of the wave, go to: http://www.wakeworld.com/MB/Discus/messages/87668/243097.html?1122768490
On our boat, for a goofy wave, we put about 1000 lbs behind the driver, 800 lbs in place of the back seat, a person sitting behind the driver, and another person in the front seat - or 300 lbs on the floor in front of the engine. Of course, what you need is a wave with good push.
I presume you read the post above. A longer board may not the answer since a longer board is less able to spin. I am 175 lbs and my board is 42" long by 19" wide. It is the world's second smallest surfboard. When I am riding hard, I frequently put the tip of the board underwater and continue surfing; that is toeside, I haven't learned to push heelside that hard yet.
If you have any more questions, please email me or call at 512.647.7321