Tonna and I have own this 1997 Advantage Sportcat.  The boat originally came equipped with a 454 Mag and Bravo drive. After a few years of stock reliable performance and 70+ mph top speeds, a few upgrades were added. The current motor is a  509 cubic inches big block. The machine work and shortblock assembly were performed by Larry's Speed & Marine in Tucson, AZ.  The motor was dialed in on the dyno and made 878 horsepower.  Top speed at this point has been a GPS verified 114.5 mph spinning a Bravo 32 pitch 4-blade to 6000 rpm. Additional prop testing resulted in the Achilles heal of the typical hot boater, a broken forward gear set in the Bravo outdrive. Once repairs are completed to the drive and the weather cooperates, further testing will continue!