The secret fuel that made the Spitfire supreme

Summary

This article in the Royal Society of Chemistry makes the following points.

• A French American, Eugene Houdry, developed a process to convert useless crude oil into 100 octane fuel.
• 100 Octane fuel increased the Spitfire's speed by 25 mph at sea level and 34 mph at 10,000 feet. 
• A 13-octane point increase contributed to the  British victory in the Battle of Britain in 1940.

References

• Media Check: About the Royal Society of Chemistry 
• Collections | The Runway (airforce.gov.au)
• ADDITIONAL READING RAAF RUNWAY (PME)
• RAAF RUNWAY: RATIONALE, GUIDELINES, LEARNING OUTCOMES, ETC