Boating Tips REPOWERING WITH NEWER OUTBOARDS OFTEN IMPROVES SPEED AND EFFICIENCY Posted 5/17/2010 There are a lot of benefits to repowering your boat, and the benefits are greater with the arrival of new-generation outboards. Take, for example, a Grady-White® 330 Express. Let's say you purchased one a few years ago with a pair of 3.3-liter Yamaha F250s. If you were to entertain repowering with a pair of new 4.2-liter Yamaha F300s, what kind of performance changes could you expect? Let's take a look. For starters, with the venerable 3.3-liter F250s, the boat will reach plane in about 10 seconds. With the new 4.2-liter F300s, that number drops to about 6 seconds. The same is true for the time from 0 to 30 miles per hour. With the F250s, the Grady-White® takes 11.5 seconds to reach 30 miles per hour. That number drops to 8.8 seconds for the new 4.2-liter F300s. Top speed improves, too. The F300-powered boat reaches 44.4 miles per hour, while the F250-powered boat tops out at 42 miles per hour. Perhaps most impressive of all is the fuel economy and cruise speed increase. At a 4,000-rpm cruise, the F300-powered boat reaches 27.6 miles per hour and returns 1.29 miles per gallon. The F250-powered boat reaches 18.3 miles per hour at 4,000 rpm and returns 1 mile per gallon. Let's look at another example, an EdgeWater® 318CC. When powered with a pair of 3.3-liter F250s, the EdgeWater® reaches plane in 6 seconds. Repowering with a pair of 4.2-liter F300s reduces the time to plane by a full second. When powered with the new 4.2-liter F300, the boat reaches 27 miles per hour at 3,000 rpm, versus 17.4 miles per hour at 3,000 rpm when powered by the F250. As for fuel economy, the F300s return 2 miles per gallon at 3,000 rpm, compared to 1.5 miles per gallon for the F250s. Y Other Benefits You Should Expect from Repowering Aside from efficiency, there are other benefits of making a switch to one of Yamaha's 4.2-liter V6 outboards. Alternator output is greater, now at 70 amps vs. the previous outboards' 46 amps. The benefit is quicker-charging batteries, which means greater peace of mind and convenience on boats that have a heavy load of electrical equipment. Based upon testing against competitive outboards, the new 4.2-liter F300 was found to have best-in-class net amperage output. It measured 29 percent higher net amperage than the nearest V6 four-stroke outboard competitor. The new family of Yamaha outboards is also compatible with the new Command Link® Plus rigging system, which uses a single 5-inch high-contrast color LCD screen to display engine, boat and other functions. Command Link® Plus not only provides convenience for the boater but reduces the amount of space used on the console by multiple gauges. A single gauge can display info for up to three outboards simultaneously. These new V6 offshore outboards use new control boxes, too, which now have push-button start/stop panels. They offer one-key operation for up to three outboards. (Quad applications use individual key switches.) For added security, the new F300, F250 and F225 are also available with Yamaha Customer Outboard Protection (Y-COP™), an electronic system that works through the outboard's Electronic Control Module (ECM) to render the outboard unable to start without the electronic key fob. When purchased with the optional Y-COP™ system, the outboard is delivered with two matched, water resistant key fobs that electronically arm and disarm the system. The new outboards are available in both 25" and 30" shaft lengths. Repowering with new Yamaha 4.2-liter offshore outboards can also significantly increase a boat's power and fuel economy. The information and data contained herein is based on Performance Bulletins prepared by Yamaha application engineers. The information and data contained herein is approximate and subject to many different factors and variables. It is provided as a guideline only and should not be relied upon as representative of actual performance. Due to various factors such as the boats actual weight, wind and water conditions, temperature, humidity, elevation, bottom paint, boat options affecting wind/water drag and/or boat weight, and operator ability, your boat's performance may be different than the information contained herein. Please confirm the performance data on your specific boat/engine combination with your dealer. Yamaha reserves the right to change performance data without notice.