Horsepower to cubic inch ratio is the easiest way to understand the personality and characteristics of an engine. As an example a 502c.i 500h.p engine produces 1 h.p/1 c.i which is a tolerable engine with good idling and does not require extensive maintenance; therefore, the engine is financially reasonable. Another example is the 572 c.i 850h.p engine, producing 1.48 h.p/1 c.i or the 705c.i/1200h.p, producing 1.5 h.p/1 c.i. These ratios may be achieved by supercharging or well designed induction systems. All these noted engines operate on pump gasoline (93 octane) and have good idling characteristics, broad torque ranges, proper assembly and quality parts. By taking these theories, we design power packages tailored to the customers needs while maintaining reliability.

In order to make a marine engine with continuing top power, precise measurements must be recognized. The ratio of Bore/Stroke is critical to endurance. Several mathematical formulae are used to establish a combination that will accept high r.p.m and provide high torque levels. Connecting rod length and wrist pin height must have exact formulations to achieve reliability and power. Furthermore, bearing clearance is determined by measurements of .0001 which detours premature wear.

Constant high r.p.m usage is assisted with a progressive, multifaceted lubrication system. Oil is sprayed onto the valve springs via a custom rail integrated into the valve cover in order to cool springs and reduce spring fatigue. Piston sprayers have a dual function, to cool the piston head and to lubricate the cylinder walls and the wrist pins. Custom designed oil pans one way screens and splash baffles increase scavenging. Five gallon sump tanks provide proper cooling and revitalization of the oil. Four oil pumps are used; three pumps remove oil from the engine at designated areas and one high volume pump with adjustable bypass allowing 125psi, inputs oil into the engine.

Chief Engines has innovated several induction systems consisting of supercharging, carburation, fuel injection, sheet metal and casted custom intake manifolds. For example, our triple dominator carb set up allots increased fuel dispersion and torque levels on the high output supercharged models. Natural aspiration requires a large carburetor, free flowing intake manifolds and cylinder heads, tuned exhaust and camshaft profiles that are large enough to allow enough fuel and air in and exhaust out. Unfortunately when the engine is running at a low r.p.m, it is actually over-fueling because the camshaft profile is large enough to allot fuel at maximum r.p.ms. Nevertheless, it is possible to design a cam profile and choose proper components to make these engines practical. On the other hand, superchargers force fuel and air into the engines and a large cam is not necessary. Consequently, small camshaft profiles increase efficiency at idle and cruise r.p.ms as well as top end power. Supercharging delivers as much torque at 2500 r.p.m as at 5000 r.p.m; therefore, fuel is burned throughout at all r.p.m ranges reducing detonation and fuel dilution.

A variety of electronic solid state, marine ignition systems fire up Chief Engines. The ignition system actually fires multiple times for each cylinder to ensure complete burn at high r.p.m and to reduce detonation. The system's capacity is 115 millijoules and 50,000 volts and if requested a complete back up system that can be initiated by a switch on the dash board.

The most unstable zone in a marine engine is the valve train/combustion chamber area. Extra care and over-building is the only way to defeat failure. Fully oiled shaft mounted rocker arms precisely installed to proper geometry are necessary. Custom ground camshaft profiles have fast ramp speeds which promote fuel/air velocity and have gentle return ramps which prevent valves from bouncing off of their seats. Valves are fabricated from Inconel and Titanium materials with special tips and locks. Valve seats are Beryllium material which aids in cooling seats and reducing seat erosion. Valve springs are subject to a cryogenic process, then coated and pressure tested. The most technologically advanced parts are implemented such as Titanium retainers, fully oiled camshaft lifters, and high quality head gaskets are essential. A composite gasket is used with an oversized fire ring that is fitted into a receiver groove; so gasket failure is prevented.|

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