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Name: John
Status: other
Age: 30s
Location: N/A
Country: N/A
Date: 2000

Does adding naphthalene (mothballs) to gasoline increase the octane rating?

The info comes from


Yes, mothballs will slightly assist the octane rating of gasoline. HOWEVER, in that grain of truth there lurks the potential for disaster. One must use very few mothballs (naphthalene only) because the ratio of carbon to hydrogen in the molecules makes for a very dirty burning fuel. Too many mothballs and your engine will load up with carbon deposits -- very bad news in the performance department.

Also DO NOT mistakenly use moth crystals (paradichlorobenzene). The chlorine atoms in this material becomes HCl upon combustion. Hydrochloric acid (HCl) is very destructive to engine internals.

Finally, unless your engine is high compression and in need of high octane fuel, enhancing the octane rating of the fuel over what is required is simply a waste of money. High octane fuel burned in an engine designed for lower octane fuel does not increase engine power.

ProfHoff 297

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