omc V6 prop choices

[bob johnson]

I have a Lowe Ultra Roughneck 2070 Mod V..... it has a 12 degree deadrise hull i had run a 115 ocean runner on it but had to keep my props pitch down at 13 and 15 to get the rpms up into the mid to high 5000's..... 2 years ago I put a 150 HP ocean runner on the boat....and i STILL seem to have to run 15 pitch to get the boat up into the 5500 range......now i guess i just accepted this: but this past weekend Im looking at some of my "extra" motors and parts and i see a 1994 EvinrudeV6 150 hp Intruder midsection and lower unit. I see it has a 4 blade SS prop on it. so i read it...it is a 13-3/4" dai X 25 pitch....TWENTY FIVE PITCH!!!!!!!!!!!! I know these motors came on a lot of bass boats..18-21 feet.....how is it they can run such a high pitch...but i cant..... they dont look much slippery than my rig... they have to actually weigh a lot more than mine too!......and or..... why do i have to go so low in pitch to get my motor turning in the right rpms at WOT????????I bought my boat brand new....

 

[Chris1956]

16-18 ft Bass boats that run those large pitch props weigh in at about 600# plus motor and have much flatter deadrise than you do. Your rig is likely 2000#, plus motor,

They also trim them to the max to get the speed they want. They are really specialty hulls to handle that much HP.

 

[bob johnson]

id say you are way off on the bass boats weight estimate.. I bet an 18 ft bass boats weighs at least 1200... maybe more than 1600 LBS!!!!!!!!! WITH OUT THE MOTOR!......my boat weighs 1200 lbs without the 380 lb V6........sooooo still wondering if the hull makes up for all the pitch??

 

[Chris1956]

Well, my 16 foot bass-style boat weighs 670# w/o motor. Not sure why 2 more feet would add 600-1000 # to the weight.

Your typical 16 foot runabout is 400# or so.

My 21 foot boat is 2200# w/o motor, so your 20 footer is a real lightweight at 1200 #.

 

[jimmbo]

Our Evinrude Sweet 16(16ft) weighed in at 800lbs for the hull
my Crestliner Crusader 550(15 ft) weighed 950 for the hull

 

[bob johnson]

rangers website says their 18 ft fiberglass bass boat weighs 1550 lbs..... Nitro offers a 16 ft bass boat but the max HP rating is only 115 hp..... so in any case....im guessing you guys are saying the boat needs to be super super light to use that much prop pitch......

 

[bob johnson]

Our Evinrude Sweet 16(16ft) weighed in at 800lbs for the hull
my Crestliner Crusader 550(15 ft) weighed 950 for the hull

the MAX hp on that boat is 95......im talking about a 150 hp motor!!!!!!!! so the boats need to be able to handle 150 hp.... to be considered...

 

[jimmbo]

the MAX hp on that boat is 95......im talking about a 150 hp motor!!!!!!!! so the boats need to be able to handle 150 hp.... to be considered...

I hung a 140 on it


I think a boat rated for a 150 would weigh even more than one rated for a 95. But you said "Your typical 16 foot runabout is 400# or so" . I posted info on two typical boats in that size range and what they weighed

 

[bob johnson]

I hung a 140 on it


I think a boat rated for a 150 would weigh even more than one rated for a 95. But you said "Your typical 16 foot runabout is 400# or so" . I posted info on two typical boats in that size range and what they weighed

that wasnt me who said that......

 

[Chris1956]

Bass-style boats are a different animal,than your typical runabout. They need to be light, strong and have a flatter bottom. The flatter bottom gives them greater speed, and max trim reduces the wetted surface further to increase speed further. They are not good for rough water.

If you see them run, you will see the bow is carried out of the water, leaving just the last 1/4 of the hull (or so) in contact with the water.


My 16 foot bass style boat with a Merc 135HPV6 can swing a 23P prop, but very few runabouts large enough to qualify for that much HP could use that much prop pitch..

 

[jimmbo]

that wasnt me who said that......

You are right, my apologies

the quote was of Chris 1956

 

[jimmbo]

Bass-style boats are a different animal,than your typical runabout. They need to be light, strong and have a flatter bottom. The flatter bottom gives them greater speed, and max trim reduces the wetted surface further to increase speed further. They are not good for rough water.

If you see them run, you will see the bow is carried out of the water, leaving just the last 1/4 of the hull (or so) in contact with the water.

My 16 foot bass style boat with a Merc 135HPV6 can swing a 23P prop, but very few runabouts large enough to qualify for that much HP could use that much prop pitch..

Kind of like my Deeper Vee I/O in my avatar... It is not over trimmed very much, you can see the bearing cap on the top of the I/O. but it is moving. and not much is in the water



My 18 ft runabout with a 150 running a 21 in prop with 25:14 gears, your 135 has what 26:13?