Alum to SS for 90HP Yamaha

[RobG]

Hi everyone,

I've got a 2007 Bluewave 190C CC boat matched with a 90HP Yamaha 2 stroke (90TLR), it came with the 13 1/4 x 17 alumimum prop. I would like to have the same if better performance with a SS prop. Any suggestions on this?

Thanks!

Rob

 

[Dhadley]

Re: Alum to SS for 90HP Yamaha

That's really hard to say without some detail but here's some general thoughts -

We'll assume some things to get started. We'll assume the top rpm, with an average load, is where you want it. Probably around 5700-5800. We'll also assume there is no jackplate. Being aluminum we'll assume it's a 3 blade. We'll further assume the motor is mounted all the way down on the transom. We'll also assume you're not talikng about skiing or tubing.

OK, now we have to know what your intensions are. Are you simply going to change props or are you willing to raise the motor?

If all you're going to do is change props, I'd probably go to a 15" prop. Something in the Stiletto line. Don't spend money on a Turbo for technology you won't take advantage of.

If you are willing to raise the motor after testing - if needed - I'd suggest a 17 Stiletto.

 

[RobG]

Re: Alum to SS for 90HP Yamaha

Dhadley,

Sorry about that. The operating rpms on that motor are around 5500. The alum prop is 3 blade and there is no jack plate.

The main purpose of the boat is for fishing and the reason i want to change it is that I'll be using it in saltwater. I've used the mercury prop selector on their website and it suggested several different sizes. the options were for top end speed, overall good performance, and good acceleration. The prop i have now is under the good acceleration category with the Alum and SS props listed. I was just curious on what other people might be using when they switched from Alum.

Thanks

Rob

 

[Dhadley]

Re: Alum to SS for 90HP Yamaha

If I were doing it and the current aluminum prop is in decent shape I'd raise the motor to see how well the hull responded and to see how many rpms I could gain. I'd hope we could stay with the 19" pitch in a decent design like the Stiletto.

That being said - if you have even a remote idea about a jackplate, now is the time to do it. Don't spend $$$ on a prop and in 6 months put on a jackplate. You might end up wanting a little better prop.