Anyone know of a decent online prop calculator for Bravo III drives?

[Whitelighter]

The V39 (we suspect) is a little under propped, and I wanted to play around with some figures before speaking to any suppliers.

All of the basic prop calcultors arent geared up to deal with counter rotating props the BIII has.

Any hot leads?

 

[neale]

Re: Anyone know of a decent online prop calculator for Bravo III drive

Not a lot of help I know, but when I need to change the duo props on my Volvo drive, 1 size up or down was said to change top end revs by around 200 rpm. I wasn't quite making max RPM so changed down a size and hit it spot on.

 

[Whitelighter]

Re: Anyone know of a decent online prop calculator for Bravo III drive

we have the opposit problem, making max revs but way down on top end. I suspect we will be going up two sizes but I just fancied having a play

 

[RobWales]

Re: Anyone know of a decent online prop calculator for Bravo III drive

Try here for a start.

http://www.mercurymarine.com/otherproducts/propellers/

or here

http://www.mercruiserparts.com/help_with_prop_selection.htm

 

[stefan_r]

Re: Anyone know of a decent online prop calculator for Bravo III drive

Also depends on which props you have....

Mercury released a prop called the "XR" that is semi lab finished and cupped...and allegedly performs better than standard.

I am going through the pain of trying to reprop my 1998 Sunseeker Superhawk on Bravo III drives.

French Marine - my local dealer - has a computer programme but you need displacement as well as all the usual measurements.

 

[RobWales]

Re: Anyone know of a decent online prop calculator for Bravo III drive

http://www.go-fast.com/mercruiser_bravo_sterndrives.htm

Good info here on post 2002 models for people who may be concerned about the B111 Drive problems.

 

[Its_Only_Money]

Re: Anyone know of a decent online prop calculator for Bravo III drive

Fill the tanks, load max peeps you would expect to carry and allow for some fouling, then see if she is under-propped.

Ask a Mercruiser dealer for the prop charts/specs, the change from what you have now should be easy to predict once you know what props you have fitted. This is quite likely to be more accurate than any prop calculator...IMHO...

 

[alt]

Re: Anyone know of a decent online prop calculator for Bravo III drive

Fill the water tank too!