I have been a long time reader/watcher and have finally decided to take the plunge in participating with you guys, so be easy on me. I need some advice. I have an Advantage 21 SR open bow, jet drive, powered by a carbureted 454/390 HP Indmar engine. My boat is primarily used for family fun (I have 3 small kids). As with anything new, I was happy with the speed (around 55) when I first got it. Now I would like a little more speed/performance (so dad can take a few 'hotlaps' for when the kids & mom pass out on the beach in the afternoon). I bought a Vortech supercharger kit last year but could not install it due to the mechanics of the kit vs my engine compartment (available space). To make a long story short, (after 6 weeks of trying to make it fit) I ended up returning the kit for a refund. I am entertaining the idea again of a supercharger kit, but this time with a Whipple. Without an intercooler, again space may be a problem for me, I am thinking that engine modifications, to support a 6 - 9psi boost (non-I/C'r), may be necessary. How many mods would be required? And are they worth it? Or would it be wiser to install a bigger engine? I do not need to go 100 mph with my hair on fire but would like to get as much speed as possible while staying reasonable with the mods & cost. Thanks.