The most common question we get with our single engine boats is “should I buy the larger engine?” The (rough) answer is quite simple. If you want to cruise all day at 20 knots, take the standard engine. If you want to cruise at 24 knots buy the upgrade. There is a fairly direct relationship between fuel consumption and horsepower. And for any given hull design and weight there is a “crouch factor” that determines how much drag that hull creates. In other words, it takes the same amount of horsepower to go the same speed, regardless of engine size. Larger engines do however permit the user to cruise faster and top out at a higher speeds. They also help the owner to adjust for boat loading and bottom cleanliness.
Here’s the performance data for the Cummins 600 QSC8.3. As soon as we have tested the Yanmar 530 and the Cummins 480 we’ll show you those too.