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Volvo Penta 225 HP 5.7 Liter
V8 Marine Engine

volvo penta's 225 hp marine engine

Boasts The Same Displacement As The
GM Marine Engine Rated 292 hp

Volvo Penta's introduction of a 350 CID smallblock V8 rated just 225-horsepower is an intriguing happenstance. The same displacement marinized GM marine is more commonly rated at a much higher output(292 hp @ 4800 rpm).

Volvo Penta's 225-horspower V8 is the cleanest gas powerplant ever offered by the Swedish marine engine builder. This single camshaft, pushrod smallblock V8 meets the stringent five-star voluntary engine emissions standards set by the California Air Resources Board. Its squeaky clean nature is due to dual, three-way catalytic converters working in synchrony with heated oxygen sensors. Similar to an automotive exhaust system, platinum and palladium convert carbon monoxide into carbon dioxide. Unburned hydrocarbons into carbon dioxide and water and nitrogen oxides are reconstituted into nitrogen and oxygen. A heated oxygen sensor goes to work sooner, as opposed to an unheated sensor that must first warm to operating temperature before it can detect rich and lean mixtures.

Find Out Why this marine engine de-tuned?

Also important to note, Volvo engineers burned the midnight oil tweaking and tuning engine calibration. More perfectly matching ignition timing and Multi Port Fuel Injection to crankshaft rpm, engine vacuum, ambient temperature, coolant temperature, altitude and other critical variables. As you would expect the engine has been knock sensors, over-rev protection other watchdog sensors. Which are monitored by the Engine Computer Module. The payoff is smoother acceleration, instant starts in all cold and hot weather and a smooth idle.

Besides its softer environmental footprint the 225-hp Volvo Penta V8 also offers miserly fuel consumption. A Volvo spokesman says fuel flow is the equivalent of its smaller 4.3 Liter V6, essentially, the engine it replaces. And because horsepower has been dialed back the reciprocating mass (pistons, connecting rods, crankshaft) makes maximum torque at a lower rpm. Lower rpm means less friction and significantly longer engine life.

I like the way the seawater pump, oil filter, fuel filter and and coolant overflow tank are mounted on the top front of the engine for easy owner access. One must-have option to the thermostat regulated raw water cooling is the closed cooling system that offers better protection against internal engine corrosion, even in freshwater.

Finally, available with joystick control, this engine was engineered to flow its ample torque to either a Volvo Penta single-prop SX drive or the renowned DPS drive.

Author Timothy Banse has published articles in Popular Mechanics, All Chevy, Pickup Van & 4-Wheel Drive, Mecanica Popular, Motor Boating, Yachting, Mar y Vela and other magazines and newspapers from around the world. He writes about cars, trucks and marine-engines.

Volvo Penta 225 Hp V8
Displacement 5.7 Liters
350 CID
Block Grey Iron
Cylinder Head Grey Iron
Bore x Stroke 4.00" x 3.48"
Compression ratio 9.4 to one
Horsepower 225
Redline 4800 rpm
Fuel 87 Octane
No more than
10% Ethanol
Redline 6000 rpm