new boat,new prop?

[cougar1985]

hey guys,i just bought a 1976 mfg gypsy star glass boat of 17feet 4 long. it weighs 1250lbs.rated for 135 hp.i have a heathly 1982 90hp rude on it with a new 17p vortex prop.also bran new tac(fiara).took out yesterday for a test run.results were 37mph(speedo)at 5500rpm with me and approx 16gallons of gas.should i stay with this setup or 15p.

 

[Dhadley]

Re: new boat,new prop?

I'd work the set up to gain the needed rpm's. Changing to a smaller pitch is the last resort to gain rpm. It might not hurt to double check the tach. Faria's are know to be (possibly) off quite a bit as are traditional boat speedos.

You're at about 18% slip now. That's not too good but not horrible.

 

[cougar1985]

Re: new boat,new prop?

yes i think your right about the tac,i know for a fact that the motor will idle at about 650to 7 as low as 5 in gear so id say the tac may be reading high by 300,is there a calibritation screw on the tac?i could put my other tac on quickly and check the diff then adjust accordingly.dhadley im also 45hp under the rating and am wondering if i may need the low pitch to perform correctly.??? ive added this thought.faira says that when off the tac should be at 6 oclock when switch turned at 0. off mine is at 8oclock.

 

[cougar1985]

Re: new boat,new prop?

im open to suggestions from anybody

 

[cougar1985]

Re: new boat,new prop?

tac was reading 350 to high will go from there

 

[Crownie2]

Re: new boat,new prop?

If that's true, than you might want to try a slightly smaller pitch. But your numbers seem pretty close.

 

[walleyehed]

Re: new boat,new prop?

I'll go with Dhadley....Tweak what you have to get the max first....It may mean raising the engine some, but that's how to get the most out of it. AND, if we go to a high quality prop in SS, it may have enough lift to increase speed and RPM so we don't have to lower pitch any..

 

[Crownie2]

Re: new boat,new prop?

I'll go with Dhadley....Tweak what you have to get the max first....It may mean raising the engine some, but that's how to get the most out of it. AND, if we go to a high quality prop in SS, it may have enough lift to increase speed and RPM so we don't have to lower pitch any..

OK - let's get a jack plate on that puppy so we can really play!!

 

[walleyehed]

Re: new boat,new prop?

That's not a bad Idea at all...I have a 6 incher on my 18ft aluminum.....with a 200.

 

[cougar1985]

Re: new boat,new prop?

playing will be next year guys. fishing the rest of this year now. took another run today ,the 15p is ok for heavy load stuff the 17p will be the main prop.now if i could only afford another 50 or so hp.lol.d thanks for all the advice, i should name this boat ,never satisified.o

 

[walleyehed]

Re: new boat,new prop?

That's the name of my boat......and my wife......

 

[cougar1985]

Re: new boat,new prop?

had a differnt name for my ex

 

[Reel-Fun]

Re: new boat,new prop?

Wow i have a sister, and had 2 girlfriends named that.


My what we have in common

 

[Texasmark]

Re: new boat,new prop?

Hey Crownie, sorry about your puppies, but we are talking about boats and engines. Not dogs. :devil:

Mark

 

[cougar1985]

Re: new boat,new prop?

have settled on the 17p vortex as the best prop for the boat.now the million dollar question. how about a solas amita 4 blade prop?what would be the difference between the 2?as ive stated this is a relitavely heavyer boat for the little 90 but until i can affor a 140hp i will live with it.as an add on ,by raising the engine will this help in controlling porpising,i have a foil on now but it still does it,or is this a trait of the tri-hull style designs?