Which Prop to Buy?

[luckyinkentucky]

I have a '94 Evinrude 200 Vindicator E200STLERK fitted on a '95 Skeeter 200SL Fish n' Ski 20' boat. My dry weight is around 1900 lbs. and my max weight capacity for passengers is 900 lbs, and it has a 41 gallon tank that stays on full at the beginning of every trip.

The prop I have on now is a Stainless Steel 4 Blade Shooter 13 1/4 X 25. My RPMs at WOT are right at 5k. How can I get the best performance out of my boat? My max speed right now is 55 mph on a calm day. I am looking for best high speed performance since I travel long distances along the river to get where I'm going. Any other time I am trolling with a trolling motor. I'd like to get up to around 5600 to 5900 rpms at WOT.

 

[luckyinkentucky]

Re: Which Prop to Buy?

bump

 

[Silvertip]

Re: Which Prop to Buy?

I think either your speed is wrong, the tach is incorrect or the prop is not a 25P. Why? The prop slip calculator says so. That speed and rpm with a 23P would yield about 10% slip. The 25P puts you into a "not possible" slip range.
Start by looking at engine mounting height and making sure the engine is putting out full power.

 

[luckyinkentucky]

Re: Which Prop to Buy?

How do I check that?

 

[Silvertip]

Re: Which Prop to Buy?

The AV plate (the flat plate just above the prop) should be as a minimum, flush with the bottom of the boat but generally and inch or two above that. You mount the engine higher to correct it. As for checking the power output of the engine, a compression check and tune-up is about all you can do. Make sure the throttle plates in the carbs are opening fully (perfectly horizontal in the carb bore). Tach accuracy is checked against another tach. Check the setting on the back of the tach. There is a dial back there. It should be set to 6P. Speed is checked via GPS.