Power Upgrade Now Prop ????'s

[Reel Poor]

Upgrading power on a 2000 Chaparral 29ft was running twin Volvo Penta 250hp 5.0Gi SX drives turning OEM stainless 19p. when boat was new engines would turn 5g, after about 300 hours the engines would turn around 5050/5100 @52mph. <br /><br />Now I'm installing a pair of Volvo Penta 320hp 5.7Gxi's. <br /><br />With the 5.0's the boat had great hole shot. I'm looking for top end and higher midrange cruising speeds. <br /><br />Any recommendations on pitch and brand. I've heard Mercruiser has some good sterndrive props. I know I would have to replace prop bushings/splines to fit, thats not a problem.

 

[Dhadley]

Re: Power Upgrade Now Prop ????'s

A lot depends on what you're looking for. I know you want more top end so bigger motors with the same weight is a good move. We assume you didn't change the X dimension or the gear ratio. If that's true then you'll most likely be looking at 21's. But a lot of that decision depends on what blade style. I'd try the new motors with the same props and see what happens. One change at a time.<br /><br />The Turbo I may be a good choice but they may have more bite than the OE ss. If you run offshore a lot you may want to consider a larger diameter (better in rough & following seas) like in the Turbo Offshore II. They are 15" diameter 3 blades.