The horsepower of a gasoline engine is rated at or near wide-open throttle, which may be at 4,500 rpm or more. Don't be tempted to make a direct comparison of horsepower between gasoline and diesel engines. Plus, gasoline is available just about everywhere, where as sometimes diesel fuel can be hard to find. They generally offer superior bursts of speed and throttle response, and they don't 'mind' going unused for longer periods of time. In addition to costing less (at least initially), gasoline engines offer maximum flexibility in drive configuration.

Diesel wouldn't make sense for these boats. Don't worry, you're not getting short-changed by having gas power as your only option. (Photo courtesy Baja Marine) However, diesel power isn't offered for the overwhelming majority of powerboats - those from 18 to 23 feet - sold each year. Outboards can be used in single-, twin- and even triple- or quad-engine applications. Far more important is the boat you buy (See related item, 'Boat Buying for Absolute Beginners, Part I' at right) and how you plan to use it. Choosing between gas or diesel power involves more than checking the depth of your wallet. You have two fundamental choices: gasoline or diesel. Gasoline or Diesel? More good news: Nuclear power isn't offered for anything a consumer can buy, solar power is rare and steam engines are out. Your job is picking the best power options from those offered for a given boat that meet your specific needs. The number crunching, at least in terms of engines offered for the boat that piques your interest, has been done for you before you walk into a dealer's showroom. So you don't need to know calculus or have a super computer to make good boat-buying decisions. Naval architects and engineers use complex formulas to determine the correct engine options for a given boat. The fact is, not every engine and drive package in say, the MerCruiser line, is offered for every boat. The Good News The choices in marine power only seem endless, especially to the novice. With so many options available, it can be difficult to decide which combination is best for you. The combination of engine and drivetrain ultimately play a major role in a boat's on-water performance.

(Photo courtesy Glastron) Powerboats run on iron hearts: twin or single, gas or diesel, outboard, inboard or stern drive. For runabouts, stern-drive propulsion packages are the most popular choice.

Inboard vs outboard vs inboard outboard