What prop do you use with 90 Merc 4 stroke

[balzacbeach]

2000 mercury 90 4 stroke,

Benny 2275, altitude 2500'.

Have a SS 15" and Alum 15"

Think I need either 11" or 13".

Have not tried the boat as just bought it in AZ and taking to new MT.

 

[kaydano]

If you know the WOT RPMs, and the rev limit on the 90, we could probably guess the better of the two for you...

 

[kaydano]

Sorry, just realized you haven't had it out yet.

You could check the props and power thread. There's likely a similar set up in there somewhere.

I would bet you are correct that the 15 is too much pitch. But not sure if the 11 or 13 would be best.

 

[bcpnick]

I had a Yamaha F90 on my last boat (last year). It came with an aluminum Quicksilver 14" x 11p prop which worked pretty well. I tried a 14" x 13p but it was lugging the motor into the lower 5k so I switched back to the 11p that brought the RPM's into the high 5k-6 range. Speed was about the same between the two. I'm at a bit higher elevation though. I was around 6k feet when I compared the two. The 13p might be good at low elevations. The 11p seemed good at 3600', the lowest I've taken my boat. 

 

[qapd]

We have the following toon with these numbers:

2010 2275 SFI
90 Yamaha 4 Stroke
3 Blade Stainless 13x14.5p Power Tech
Crockett, Tx
23.3mph/gps