350 hp...... well maybe.
The Champ and drag motors use the same block and rotating assembly. The drag runs an SVS and 26cc heads ( 180 lbs compression ), the S3000 is a left hand motor ( no hp gain, though some say there is 5 hp..... I have never seen it on the dyno ), has a horn induction and 36.5cc heads ( 140 lbs compression ).
The ECU is limited to 8600, unless you have a euro spec motor where it is 9650....... but you need to run an SVS, or the ECU vacuum resolution will be off. The drag is limited to 11500................not that the rods will let you get there.
realistically the motors are 330-340 hp ( at the flywheel )..... high 300's if modified and on race gas, over 400 if bored and stroked........ any way you look at it, that boat is just stupid in the power to weight department.......... when can I get a ride?