Gasoline Injection Fundamentals

Gasoline is the most common type of automotive fuel. It is an abundant and highly flammable part of crude oil. Extra chemicals, called additives (lead, detergents, antioxidants, etc.), are mixed into gasoline to improve its operating characteristics.
Leaded ad unleaded gasoline
Leaded gasoline has lead antiknock additives. The lead allows a higher engine compression ratio to be used without the fuel igniting prematurely.
Leaded gasoline is designed to be used in older cars which have little or no emission controls. They were not required to pass strict air pollution standards.
Note! The lead additives in gasoline also act as a LUBRICANT. The lead coats the face of the valves and seats in the engine, helping to prevent wear.
Unleaded gasoline, also called no-lead or lead-free, does NOT contain lead antiknock additives. Congress passed laws making cars meet strict emission levels. As a result, auto makers began using catalytic converters (device in exhaust system for treating exhaust emissions) and unleaded fuel.
Lead additives cannot be used in a car with a catalytic converter. The lead will coat the inside of the converter and prevent it from working.
If unleaded fuel is in a car designed for leaded fuel, it can increase valve and seat wear.
Only use the type of fuel recommended by the auto maker.
Gasoline Injection Controls there are three common methods used to control the amount of gasoline injected into the engine: electronic controls, hydraulic controls, and mechanical controls. Older gasoline injection systems use a combination of each.
Electronic fuel injection control uses various engine sensors and a computer to control the opening and closing of the injection valves. This is the most modern and common type of gasoline injection system. It will be covered in detail.
Hydraulic fuel injection control refers to hydraulically (air or fuel pressure) moved control devices. Hydraulic control uses an airflow sensor and a fuel distributor.

Gregory Lorson

https://gregorylorson20.wordpress.com/2012/03/07/gasoline-injection-fundamentals/

Security and the Struggle for Power

To maintain law, order, and security, the cornerstones of prosperity and culture in the Near East, centers of political power arose in the valleys of the Nile, the Tigris and the Euphrates. the Egyptians evolved a national state, and the Sumerian city states, but eventually in both Egypt and Mesopotamia empires were organized, which strove in vain to achieve domination of the Near East. The wars between these imperial states tended to undermine the security necessary to economic well-being.

It was not until the sixth century B.C. that political integration of western Asia was achieved by the Persians. Having secured control of the southern and eastern land the Phoenicians, attempted to wrest from the Greeks the northern and western trade routes. The conflicts which followed are known to us as the Persian Wars. This inconclusive struggle, which left the Persians in control of most of western Asia and the terminals of the Asiatic trade routes while the Greeks retained domination of the Aegean and Mediterranean sea lanes, created an unstable situation, which was unsatisfactory to the ruling classes in both the Persian Empire and the Greek city states.

Ostensibly, the Greeks were fighting for Hellenism and the Hellenic way of life against the “barbarian” Persians. The struggle had the superficial appearance of a conflict between the political individualism of the competitive Greek city states and the political totalitarianism of the multinational Persian Empire. The actual stakes were the control of the Near East, with its rich centers of industrial production and its intercontinental trade routes. The impasse was resolved 148 years later by Alexander the Great in 331 B.C. After bringing the Greek city states under subjection, he rapidly conquered Egypt and destroyed the Persian Empire, in an endeavor to create an imperial state embracing all the Near East, plus Iran and Central Asia.

Gregory Lorson
https://gregorylorson20.wordpress.com/