#pre-ignition

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Amsoil P.i. and Upper Cylinder Lube

Amsoil P.i. and Upper Cylinder Lube

P.i and Upper Cylinder Lube work in tandem to address common issues many drivers encounter. Both can be used together. Decreased fuel economy Increased exhaust emissions Power loss Poor starting and rough idle Pre-ignition “knock” or “pinging”

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Detonation

For those of you who don't know what detonation is, here's a quick summary of what it is and what it can do to your engine.  But before I start summarizing, it's generally good to know that detonation is never a good thing. If someone tells you your engine has been on the verge of detonating or is already detonating, you'd best get that checked before you kiss your car's engine goodbye.  

Engine knock (detonation) is what happens when the air/fuel mixture in the cylinder starts off correctly as a consequence of the spark that the spark plug sends, but then one or more pockets of air/fuel explode outside the envelope of the normal combustion front (i.e. some pockets of air/fuel explode outside the combustion chamber--a volume specifically set around the top of the cylinder for where the air/fuel mixture combusts--during the power stroke).  So what happens when engine knock (detonation, ping, etc.) happens is that the fuel gets out of control and starts combusting incorrectly after the spark goes between the compression/power strokes. The result can range from inconsequential to catastrophic (like blow-your-engine-up-and-create-holes-in-the-block-and-pistons catastrophic). Octane rating is the rating of fuel to RESIST engine knock. So 114 octane would resist detonation much better than regular 87 octane we fill our cars on. Why do higher octanes resist engine knock? I'm not quite sure, but i think it's because they have more carbon chains than the lower octane ratings, so it takes a higher pressure, volume, and temperature to make them combust.  Every chemical reaction has an activation energy. Some reactions start spontaneous, some need a catalyst or added energy (usually heat) to start the reaction. What goes on in the engine is that in order to explode the air/fuel mixture, the spark plug gives the activation energy under high pressure, temperature, and low volume conditions to explode the mixture.  When you have a high compression ratio (CR) (which is basically the units of air/fuel mixture the cylinder is taking in during the intake, compared to the one unit it's compressed into during the compression stroke) engine and fill it with low octane pump gas, the octane cannot handle the compression and starts exploding (or ping-ing) erratically, which can blow holes through the block and pistons.  An easy misconception is that pre-ignition and detonation are the same thing. They are not; pre-ignition means that the air/fuel mixture starts exploding before the spark goes and detonation means that the air/fuel mixture starts exploding after the spark goes. In both cases, the explosion is happening outside the combustion chamber (which is bad).