Need help choosing Mercury prop

[GlenP]

Performance Issue I would like to correct: I want to purchase a Mercury Stainless Steel 3 or 4 blade prop with close to the same WOT and MPH (or better) as the Black Max mentioned below that came stock with my new boat. Both Stainless props tested took longer to get out of the hole and acceleration and speed diminished as well.
I like how the Black Max performs- I just want the same performance in stainless.
Please note the stock Black Max runs over the recommended WOT.

2012 -224FSX Monterey Runabout Open Bow
Total Avg weight 4400 lbs
21? LOA
8? 6? Beam
2012 -220 HP 4.3 MPI Mercruiser fuel injected
Alpha 1 1.62 gear ratio
WOT RPM Range 4200-4800
Tested at Sea Level and 500? on glass/no wind/full trim with same results
All brand new props

Test results for 3 different props:

Mercury Black Max m/n-832830A45
3 Blade Aluminum
14.5 X 19
WOT 4900 RPM
MPH 50

Mercury Revolution 4 m/n-857026A46
4 Blade Stainless
14.625 X 19
WOT 4200 RPM
MPH 40

Mercury Enertia m/n-899000A46
3 Blade Stainless
13.8 X 20
WOT 4200 RPM
MPH 42
(Steering wheel wobbles-shakes at 1000 RPM-don?t like)

 

[jestor68]

Re: Need help choosing Mercury prop

The Mercury Vengeance SS prop is the closest in design to the Black Max aluminum prop.

It should run 100-200 rpm slower than the aluminum 19, while giving a slight boost in top speed as well acceleration.

I'm talking about using the same pitch in 3 blade, since you're slightly over on rpm.

A list of Mercury SS props best matching the performance of the al 14.5 X 19 would be:
Vengeance 14 X 19
Rev 4 14.6 X 17
Inertia 14 X 19

 

[jestor68]

Re: Need help choosing Mercury prop

WOT RPM Range 4200-4800

That would be 4400-4800 rpm for a WOT rpm range.

 

[GlenP]

Re: Need help choosing Mercury prop

Thanks Jestor.

Good catch on the WOT range!

Glen

 

[GlenP]

Re: Need help choosing Mercury prop

Posting to follow up with thread. Purchased new Mercury Vengeance 3 Blade 14 x 19 SS.

Tests results:

Light chop
WOT 4800
MPH 52
Smooth operation all ranges
Acceleration improved over Black Max AL
Out of Hole 4 sec

Thanks Jestor! I'm staying with this one.