Hydrostream Viper ??

[horn5413]

A friend of mine just bought a Viper with a 115 Merc no jack plate and a standard 23 pitch SS prop. His question is the boat is porpousing bad at speed, and would a jackplate or different prop help, or is this normal for this rig. Thanks Mike

[Paul Vaillancourt]

Mine can propose real bad but it seems like it happens most between 40 to 55 mph as long as i'm going faster it goes straight as an arrow. A jack will make things better and worse. By setting the motor back it will cause more of a propose, but you can lower the motor with a hydraulic jack and the porpose will go away but you will feel the hull dragging in the water.

[EMDSAPMGR]

The porpoising has always been a "normal" problem on the Hydrostreams. Removing the hook in the bottom may help reduce your problem. It also may reduce your high speed potential. You need to decide which you want. I'd live with the porpoising and keep the hook-it is there for a reason.