prop

[jerrdog]

Hello I have a 1986 bayliner capri cuddy/w 1986 85hp force, what kind of speed should i get with a 17 pitch or 19 pitch how can I get the most out of my 85hp, dont have a tach yet, kind of hard to find a 20 pole.

Thanks

 

[steelespike]

Re: prop

Really difficult to tell without a base line max rpm, speed and prop.
From the little I've read I would guess between 25-30 mph.
It would also seem that 17in pitch would be near the max for that setup.
perhaps you could borrow a gps and a shop tach or get a tech to do a quick rpm /speed check.Probably cost a few bucks but without there no good way to know where your at.

 

[Frank Acampora]

Re: prop

Depends on which length cuddy you have. Obviously, a 20 footer will go slower than a 18 or 19 footer simply because it has more weight. And speaking of weight, speed is also dependent on how many people and amount of gear you are carrying.

That said, Your engine is probably rated to run at wide open throttle at a range of 4500-5500 RPM. Since your 85 should have 2 to 1 gearing, at 5000 RPM, the MAXIMUM theoretical top speed with a 17 pitch prop is 40 MPH. Given at least a 10% slip factor, the BEST you could expect would be 36. That is an optimistic BEST estimate. You would probably be doing very well if you got 32 MPH top speed. And that's assuming your engine has the poop to turn 5000.

 

[jerrdog]

Re: prop

My boat is a 15.7 foot, with 2 adults in it.

 

[Silvertip]

Re: prop

How long is it with just you in it?? -) Gosh I'm sorry. I just couldn't resist that!

 

[oregonorbust]

Re: prop

that was funny!!!

 

[Frank Acampora]

Re: prop

LOL!!! Silvertip, you're getting evil.

Teleflex makes a 20 pole tach for that engine--right here at iboats--I forget the part number. Maybe someone else can get it for you. Search the previous posts. It was discussed about a month ago.

 

[jerrdog]

Re: prop

How long is it with just you in it?? -) Gosh I'm sorry. I just couldn't resist that!

Thats how it always is just a couple of inches to short....to make it an even 16 foot(get your mind out of the gutter!) : < )

 

[Frank Acampora]

Re: prop

Coast Guard regs break at 16 foot, so by making the boat 15.7 they fall under the smaller boat regs yet you have essentially a 16 footer. For example: under 16 foot, you are not required to have a throwable preserver.