will this help performance

[oldfordcrap]

hi this is my first post i have a 1985 42ft excalibur eagle twin 540s 1200hp offshore i also have a pair of i believe thay are called manta ray fins from a previous boat with twin 235 evinrude outboards they mount on the lower units just above the props my question is will thisbe of any benefit to my big offshore and are they worth installing thanks for any help or ideas Ralph

 

[26aftcab454]

Re: will this help performance

welcome to iboats---what kind of improvements are you looking for??
-the fins might get you on plane faster-run slower rpm on plane --but might cause more drag at top speed and on a heavy boay like yours may put alot of stress on the lower drives.

 

[Lion hunter]

Re: will this help performance

Count me as ignorant but does a 42' boat do anything other than plane?

 

[Lion hunter]

Re: will this help performance

Yeah, I am ignorant on that too. I just can't see the need to worry about getting a 42' boat on plane.

 

[DuckHunterJon]

Re: will this help performance

" I just can't see the need to worry about getting a 42' boat on plane. " -- especially with 1200 HP!!

I would leave the fins in the basement, can't see them doing you any good and as was said, they could put too much stress on those drives.

 

[Bondo]

Re: will this help performance

hi this is my first post i have a 1985 42ft excalibur eagle twin 540s 1200hp offshore i also have a pair of i believe thay are called manta ray fins from a previous boat with twin 235 evinrude outboards they mount on the lower units just above the props my question is will thisbe of any benefit to my big offshore and are they worth installing thanks for any help or ideas Ralph

Ayuh,... I kinda doubt they'll do a danm thing for the handling of your boat,....
But,....
They'll be Great for laughs at the dock.....
Especially if you trim way up, so your Hot Boat Buddies can see 'em....

 

[oldfordcrap]

Re: will this help performance

hi my boat has trs drives and ive had it up to 60 mph on gps last year just hope to get a few mph for free !!!!! i was also under the impression that these fins reduce cavitation and help with drag .when i had them on my 29 ft with 2x235evanrude out boards they lowerd rpm by say 150 and top end by 3-4 mph (incresed) thanks for all your replies

 

[Gary H NC]

Re: will this help performance

The fins will NOT get you any more speed...With that much power the best they will do is break and damage the drives.
They can also cause dangerous handling problems.

 

[oldfordcrap]

Re: will this help performance

The fins will NOT get you any more speed...With that much power the best they will do is break and damage the drives.
They can also cause dangerous handling problems.

thanks for the information! Ralph

 

[26aftcab454]

Re: will this help performance

hi my boat has trs drives and ive had it up to 60 mph on gps last year just hope to get a few mph for free !!!!! i was also under the impression that these fins reduce cavitation and help with drag .when i had them on my 29 ft with 2x235evanrude out boards they lowerd rpm by say 150 and top end by 3-4 mph (incresed) thanks for all your replies

a buddy of mine had a 43ft Excaliber w/454s and would leave a 6ft deep hole in the water behind the stern-way cool!

 

[oldfordcrap]

Re: will this help performance

yea its a monster one thing that shocked me was that it gets about the same gas milage as my last boat 29ft 2x 235s evanrudes

 

[lkbum]

Re: will this help performance

Hope this helps some of the previous posts, if the water is seperated from the transom, you are on plane. Below plane, the water is "attached" to the hull and you are displacing the water as you travel through it. If you go fast enough (and this can be pretty slow depending on design), the water will seperate from the transom, exposing it and you are now on plane.