Whale tail for just above the prop, worth it?

[SCStripers]

Whale tail for just above the prop, worth it? I have a 85HP 1978 Evinrude and thinking about buying some. Do they really help with planing out faster? Will they slow the boats top end speed? does it cause bad Cavitations?

 

[RICKRICK1]

Re: Whale tail for just above the prop, worth it?

Yes, some not much, and no. Most will help get a boat on plane faster as they tend to hold the bow down more. You will lose some top end on smaller motors, on your 85 hp you will not lose more than 1 or 2 mph. I prefer the dole fin as it is smaller and has less resistance thru the water. I haven't noticed an increase in cavitation.

 

[CDBLAZERS]

Re: Whale tail for just above the prop, worth it?

Forgive me I am new to boating but I have been told to buy one of the hydro fins for my boat to help it plane faster.....But what is cavatation? and is it a bad thing? I have an 85 force on a 16 ft 1985 bowrider boat.<br /><br />Thanks

 

[hunt-fish.com]

Re: Whale tail for just above the prop, worth it?

I have a StingRay on my 115 Johnson. It planes much faster. No noticable speed loss. Pulls skiers better. No cavitation problems. The hard plastic will give you a good scratch when getting back in the boat if the water is choppy and your not careful.<br /><br />John<br /><br />Cavitation is when too many air bubbles get to the prop due to altered water flow. You'll notice the prop will seem to slip when this happens.

 

[Dhadley]

Re: Whale tail for just above the prop, worth it?

Keep in mind the fins are a tool that allows the motor to be run at a higher X dimention. Install the fin, raise the motor and you should end up with a higher top end speed as well as a better holeshot. The bigger the fin the higher you can raise the motor. <br /><br />Good luck!

 

[SCStripers]

Re: Whale tail for just above the prop, worth it?

Thanks everyone.....Dhadley when you say raise the motor....are you saying to trim it up with the trim and tilt? or phz mount engine higher on the boat?

 

[Dhadley]

Re: Whale tail for just above the prop, worth it?

Raise the motor on the transom. IE - if the bolts are in the top hole, raise the motor and reinstall the bolts in the 2, 3 or 4th hole. Depending on the technology of your prop and which fin you use you may be able to go even higher via a jackplate.<br /><br />Not knowing what boat you have this a bit of a guessing game. Start by running the motor where its mounted now. Write down everything from top rpm, load, water pressure, speed, water conditions, acceleration, cavatation (if any) and "feel". Then raise the motor and test to compare. Its actually a lot of fun.<br /><br />Good luck!