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IMPORTANT INFORMATION ON DETONATION
Detonation is a phenomenon that can occur in any gasoline engine. It is distinctly different from Preignition.
Detonation is caused by incorrect or excessive engine timing, engine temperature, cylinder pressure, fuel
mixture temperature or fuel octane rating.
Detonation is defined as a spontaneous combustion of the remaining fuel air mixture occurring after normal
combustion occurs. When Detonation occurs, it causes a very high, very sharp pressure spike in the cylinder.
That pressure spike results in the components of the engine resonating as if they were struck by a hammer.
This noise of detonation is commonly known as “spark knock” and is not always audible under normal driving
conditions. (The main reason for knock sensors).
What will be noticeable is the loss of power, increased engine operating temperature and in some cases,
smoking.
Please review the following photos that illustrate the results of detonation on a gasoline engine.
Failure of an engine from the effects of detonation is not covered under the RMP warranty.
Pistons with broken ring lands are one of the first effects of Detonation
Detonation Information
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The underside of the piston crown is heavily discolored with coked oil due to excessive heat
being transferred.
Detonation Information