Improve MPG: The Factors Affecting Fuel Economy
- Presents a methodology to assess engine's performance as well as one's own driving habits to improve driving efficiency.
- http://www.omninerd.com/2006/07/16/articles/57

Auto Math Calculations
- Features technical articles and several calculation tools for evaluating the thermodynamic efficiency of engines.
- http://www.smokemup.com/auto_math/

Internal Combustion Engine Simulator
- Visual applet simulating a four stroke Otto engine, with user changeable parameters. Shows the Carnot cycle and thermodynamic measures.
- http://ir.chem.cmu.edu/irproject/applets/engine/

Wikipedia: Carnot Heat Engine
- Free encyclopedia article explaining the Carnot cycle, with emphasis on engines.
- http://en.wikipedia.org/wiki/Carnot_heat_engine

Carnot Cycle
- Explains the basics of the Carnot cycle. Includes thermodynamic diagrams and theorems.
- http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/carnot.html

Four Stroke Internal Combustion Engine
- Explains the strokes of internal combustion engines using animations from the Glenn Research Center.
- http://www.grc.nasa.gov/WWW/K-12/airplane/engopt.html

Kruse Limited Temperature Cycle
- Describes an innovative thermodynamic engine cycle which limits peak combustion temperature in direct injection petrol, gasoline and diesel engines. Includes engine cycle overview and description, references, diagrams and patents.
- http://www.kruse-ltc.com

Wikipedia: Internal Combustion Engine
- Free encyclopedia article covers internal combustion engine technology and applications. Addresses operation modes, thermodynamic cycle and efficiency, fuel types, support systems and parts.
- http://en.wikipedia.org/wiki/Internal_combustion_engine

HowStuffWorks: How Car Engines Work
- Explains the basics of Otto cycle engines. Include technical drawings and animations.
- http://www.howstuffworks.com/engine.htm

HowStuffWorks: How Automobile Ignition Systems Work
- Explains the basics of ignition systems in Otto cycle engine. Includes technical animations and drawings.
- http://www.howstuffworks.com/ignition-system.htm

ASME: Internal Combustion Engine (ICE) Division
- Encourages research, development and data exchange among its members. Includes events, publications, codes and standards, and contact information.
- http://www.asme.org/divisions/ice/

HowStuffWorks: How Does a Miller Cycle Engine Work
- Explains the technical and historical background of the Miller cycle.
- http://www.howstuffworks.com/question132.htm