ondtip

1987 Seebold 20' Ski Eagle has a 1987 Johnson GT 200 with a 4 blade OMC Shooter prop. I have read this prop is not designed to surface, but I might try it anyway. Max RPM is 5600 at 65 MPH on GPS. As it is trimmed up, while at full throttle, it is tight until enough trim then it loosens up and starts to porpoise. There is a very fine line between tight and when it starts to porpoise. The prop shaft is about 3 inches below the bottom of the hull. I was thinking I need a 3 blade with out the hub, chopper style and raise the engine to get more speed. I know many of the big cats porpoise but you need to power through it then it smooths out. I am thinking I need more speed to get through the porpoise. What prop and height works on these hulls? I know it needs a "Black" engine, but I have a white one for now.

floatingphil

I had one years ago and it was super solid at all times. If I recall it would porpoise slightly around 50 on it's way up and that was it. Mercury 200 with a powerlift and a 26 Mercury chopper that I sent to Seebold and they worked it a bit for me. That hull has a lot more potential than 65 mph. Have fun with it!

Big Block

Start at 1/2" above the center pod and find you a good Yamaha drag prop. That boat will run well if set up properly.

FunHome

Great question to post on
ScreamandFly.com

Lost of outboard guy on there!