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Have a 2011 150 Super Sport with the 60Hp Bigfoot...13.75 X 15 aluminum prop. Seem to only get 4800-5000 RPMs with two small people and 200 lbs of gear. Wondering if I would see significant improvement if I replaced the prop with a 13 3/8 X 14 vengeance SS? As a new Whaler owner...suggestions greatly appreciated.

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On the performance page of whaler.com for the 150 super sport, it shows a WOT rpm of 5940 and speed of 36 mph with a light load and the same prop you have.

Cf:http://www.bostonwhaler.com/boat_grap...nePerf.pdf

While the whaler test is a light load with warm temps and idilic conditions, your report reads sub par.

Are the passengers and gear distributed?
Are you using the engine trim (out) after getting on plane?

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The weight distribution could be a bit better but only by having the extra tank of gas moved to the port side rather than beside the original gas tank. I played extensively with the trim, with the load mentioned, and could rarely get to the 5000 RPMs...I did break 5100 RPMs once but could not get it to preform at the level a second time. Was thinking the SS prop would help??

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4800 rpm's is making me think something is wrong.

Before we address a loaded boat, how does the boat perform (wot RPM's and speed) with just you?

Are you certain of the prop or just recalling what came on the sales slip. It is possible the prop is not what should be there. If you remove the prop and look on the inside of the hub it lists the numbers.

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The Mercury website states that the 60hp Bigfoot WOT RPM's should be between 5500 to 6000.....
http://www.mercurymarine.com/engines/...0/?model=5

You don't seem to be getting the WOT RPM's with the prop you have now.

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Agree with others - something is wrong with motor or boat. Engine not running properly? Boat bottom have any issues, or waterlogged?
My 15 Sport with a 70hp Evinrude can spin a 13.25 by 19 stainless up to 6000rpm. I know it is not same engine, but that 60hp should be able to turn a 15 pitch much faster than that.
Did it ever run better or turn more rpm's? Possible that you have wrong tach and/or tach settings?
Can you try a different tach to confirm?
If you GPS your speed what do you get?

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Let's make sure we compare apples to apples.

The latest version of the 150 super sport has a dry weight of 1700+ lbs and a different hull than the prior version of the 150 and is vastly different than the classic 15 sport.

The Mercury 60hp motor has a gear ratio of 2.33 to 1

The author has a brand new 2011 boat. I highly doubt the tachometer is faulty at this stage of the inquiry.

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Checked the prop numbers...they are correct...13.75 X15. The boat is new and only has about twenty hours on it. The RPMs when I'm alone is still about 5000. Guess I should bring it into the dealer to have it checked out...unless there is something I can do.

Assuming I get the RPM issue solved and wanted a stainless prop for a little more speed and tube towing....is the Vengeance 13 3/8 X 14 an effective choice for the motor and boat?? Thanks for your assistance.

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You need to resolve why your boat/motor is not hitting the last 1000rpm before changing props. The prop you are asking about will still probably not reach the recommended operating range from data you have given.