The Viper was made i believe 3 years '91 '92 '93 its hull design is most closely related to the Panther model which ended production in '89 also the Scarab Sport 30's have a very close if not identical hull bottom. The Vipers are flat decks(no hatches) where as the Excel and Thunder models have hatches.
As far as speed anyone here will tell ya that depends on a lot of variables, my '92 Viper ran a consistant 88 on radar w/ twin 468 ci's SC's (650hp each)and Bravo's. And props thats another variable that you'll have to play with.
I do believe there were Kevlar layups although not many, mine was not one of them.
Good Luck with the search for your boat.