i have an '88 sunsport and i still run 650 front, two 800's in the back with maybe 100lbs out of the non-surf side. your boat is heavier than mine so it will take more to sink and get the same wave, so i'd say you need at least this amount of weight at a minimum. i also have a surfgate installed. i'd say start with adding 600lbs up front, with the current amount of weight you have in the back.
'88 Sunsport, 2250lbs ballast, automated surf system, home made surf exhaust, surf flap, ACME 913, Krypt 6.5 HLCD's, Perfect Pass Stargazer
2007 Centurion Typhoon to be upgraded this winter!