![]() The Enertia is offered in 1-inch pitch increments, rather than the traditional 2-inch increments, to really fine-tune top rpm. We ran Enertia to try a different-style prop and also to demonstrate the effect of changing prop pitch. Max economy: 6.07 mpg 3,251 rpm/22.4 mph Boating Magazine Enertia 14 7/8″ x 16″ Stainless steel, three blade, 14 7/8″ x 16″ Top Speed/Light: 44.9 mph 5,812 rpm For general-use boating, overall smoothness is the key advantage of a four-blade prop. There’s pronounced bow lift at the last 5 percent of the trim range, it holds well in turns, and it offers better reverse thrust than the Tempest Plus. That said, the Rev 4 feels great from the helm. That might be true on a faster or heavier boat, but in a more modestly powered rig like ours, the difference in performance between these two props is negligible. ![]() The extra blade should also produce more drag and thus lower top speed. Merc also recommends the Rev 4 for stepped-hull boats, which send a lot of frothy, aerated water to the props. The Rev 4 is very popular on twin-rig outboard offshore boats because it really holds well in rough water, especially in following seas that can lift the transom and ventilate the prop. If three blades are good, will four be better? To find out we ran the Revolution 4, sort of a four-blade cousin to the Tempest Plus designed to deliver better hole-shot acceleration than the Tempest simply because it has more blade area. Max economy: 6.09 mpg 3,250 rpm/22.0 mph Boating Magazine Revolution 4 Stainless steel, four blade, 14 5/8″ x 17″ Top Speed/Light: 41.9 mph 5,766 rpm The Tempest will also be much more durable than an aluminum prop. But the boat felt really planted and steady in the water and handled well. In our testing, I noted that the Tempest seemed to take less trim than the other stainless props and produced a little less lift. All of those design elements are critical to maximizing performance on an 80 mph bass rig but become less impactful as boat speed slows down. To boost speed, the Tempest Plus has aggressive rake to promote bow lift and less blade area to reduce drag. The 17-pitch model we tested is actually the smallest pitch offered - a fast bass boat will run a 25-pitch Tempest Plus. To move up to stainless steel, we chose the Tempest Plus, a performance three-blade boat propeller designed to produce good top speed and a popular choice with tournament bass and walleye anglers. Max economy: 5.80 mpg 3,253 rpm/23.7 mph Boating Magazine Tempest Plus Stainless steel, three blade, 14 5/8″ x 17″ Top Speed/Light: 45.9 mph 5,779 rpm Made of aluminum, it’s easy to ding up, even beyond repair, with a bottom strike. I had to trim down to keep the prop from losing bite on the water even when making modest turns - and it blows out immediately when over-trimmed. When running the Black Max, I noted that spray was breaking off the hull forward of a gunwale rod holder, while it broke 18 inches abaft the same rod holder with every stainless prop we tested. The Black Max does not produce the lift of a stainless-steel prop. In our testing, it was significantly slower than the stainless-steel props but matched the acceleration of much more expensive options. Blade flex and modest cupping cause the Black Max to slip more than most stainless-steel props. The Black Max is a generalist, with conservative geometry, designed to deliver acceptable performance in almost any situation. It’s standard-issue from boatbuilders paired with the MerCruiser Alpha sterndrive and outboards up to about 135 hp. The three-blade aluminum Black Max is the best-selling propeller in the world. Max economy: 6.09 mpg 3,250 rpm/22.0 mph Boating Magazine Black Max We tested each boat propeller “light” (just the tech on board) and “heavy” (with 350 additional pounds in the boat), always with the 60-gallon fuel tank full.Īluminum, three-blade, 15″ x 17″ Top Speed/Light: 41.9 mph 5,766 rpm ![]() From the site’s “wall of props” we chose six Mercury propellers to test, and then bundled up on an October morning and motored out to Lake Butte des Morts. ![]() From its Oshkosh, Wisconsin, testing facility Merc offered us the use of a 1,900-pound Key West 2020 center-console rigged with a Mercury 150 FourStroke outboard, and a full complement of data acquisition gear. So it’s useful to offer another installment of prop basics, an attempt to answer these most elemental and popular propeller head-scratchers, this time using an outboard-powered fishing boat and a selection of props from the vast inventory of Mercury Marine. You can do your own testing with a GPS and a stopwatch, but also pay attention to how the boat feels with each prop. Choosing the Right Prop Selecting a Prop Dealer Find a dealer that will let you test-drive a number of props before you buy. ![]()
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