Moderated Discussion Areas
ContinuousWave: Whaler Performance
|Author||Topic: Nantucket re-prop|
posted 09-13-2004 07:47 PM ET (US)
Ok... I changed the prop on my Nantucket w/150 Optimax from the 15.5x17 Mirage Plus to a 4 blade PowerTech OFS200 15.5x15 with 5/16 vents. I ran both the Mirage and Power Tech props at 500 rpm increments from 1500 to max rpm on a two way course as to cancel current and wind factors, weight and temp was nearly the same. All numbers were obtained with a GPS and smartcraft gauges.
The performance change was significant, for the better! The bad news is I lost 2.2 mph on the top end, as I expected (from 43.8 to 41.6). However, I have MUCH less bow rise and the engine is MUCH smoother. There is no more clanking or gear noises when going from neutral to forward or reverse. The time to plane is considerably less and I hold plane 4 mph slower. Acceleration is astounding and you really have to try hard to vent the prop in hard high speed turns. Mid range (2500 to 3750 rpm) speed increased 1 to 3 mph depending on the rpm and what surprised me is at 3500 rpm my fuel flow dropped by 1.1 GPH thus increasing my range by 54 miles. I guess it doesn’t take near as much throttle to obtain 3500 rpm as with the Mirage. I would HIGHLY recommend this engine/prop combination to all 150 Opti owners.
p.s. - I can turn 5790 rpm with the new prop, I may send it back for some tweaking to reduce the rpm to 5650 or so. Doing this should add 2 mph while maintaining the midrange numbers. Will probably wait until its gets cold here to do this mod.
posted 09-13-2004 08:09 PM ET (US)
You should look at Mercury's comparison reference on three blade vs four blade prop selection. You have described the benefits and shortcomings perfectly, just as they indicate.
It seems to make sense that a buyer of a new Whaler could have options, based on these comparative properties, of which type prop they wanted furnished with the boat/engine purchase.
posted 09-13-2004 09:05 PM ET (US)
It was a bit difficult to locate the propeller you are talking about on the PowerTech website. The part number you gave is not quite correct. I think you are talking about:
posted 09-13-2004 09:07 PM ET (US)
posted 09-14-2004 12:37 AM ET (US)
jimh...the last link is correct. sorry.
posted 09-14-2004 08:31 AM ET (US)
That is a pricey propeller! Do you buy direct from PowerTech or from distributor/dealers?
posted 09-14-2004 08:55 AM ET (US)
I ran the same prop on my 21 Outrage with the same results. Very impressed with the prop. Pitch is too low, I may replace with higher pitch.
If you go to the Mercury parts express section on their website, they will be happy to sell you a Mirage for about $600 or a REV4 for about $640. Most local Mercury dealers I have contacted charge Mercury list price for propellers.
I paid around $430 for my Powertech on the internet. About the same price as a Mirage or a REV4 "on the net".
posted 09-14-2004 02:49 PM ET (US)
For the best pricing on Mercury performance props, see kenyonpowerboats.com. All are $400, except for the Revolution 4, which is $450. I think this includes hub insert brand of your choice.
posted 09-14-2004 03:36 PM ET (US)
Kenyon is the best pricing I have found, ordered from there on a recommendation from this site. My Mirage was $400 plus shipping. Speedy service too!
posted 09-15-2004 11:46 PM ET (US)
Larry [ LHG ], e-mail me.
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