Craig's a farmer, farmers fix their own equipment if at all possible and farmers are usually the first to help someone out if they can.
To CPrince
for any advice or suggestions, thanks neighbor
Pre-detonation
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Hollywood
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And yet nobody has explained predetonation??
If I am correct, it happens when you burn low octane fuel in a high compression engine. Since lower octanes ignite at a lower pressure, they explode in the chamber before the plug fires causing a double firing of the piston. This can cause serious damage to the engine over time and at the very least, a big loss in horsepower. Thus, you can burn 91 octane in an engine rated for 87, but not the other way around.
AM I right? Do I win the prize?
If I am correct, it happens when you burn low octane fuel in a high compression engine. Since lower octanes ignite at a lower pressure, they explode in the chamber before the plug fires causing a double firing of the piston. This can cause serious damage to the engine over time and at the very least, a big loss in horsepower. Thus, you can burn 91 octane in an engine rated for 87, but not the other way around.
AM I right? Do I win the prize?
Fishing is a heritage we need to teach. Take a kid fishing! And take me too while you're at it.
Thanks Myles. So it turned out the word has a meaning. Some lesson for all the experts among us to learn.
On another note. Got skunked last week. Going again today, fingers crossed.
BM
On another note. Got skunked last week. Going again today, fingers crossed.
BM
"The time has come," the Walrus said, "To talk of many things:
Of shoes--and ships--and sealing-wax--
Of cabbages--and kings--
And why the sea is boiling hot--
And whether pigs have wings."
Of shoes--and ships--and sealing-wax--
Of cabbages--and kings--
And why the sea is boiling hot--
And whether pigs have wings."
Confusion and a lot of questions exist as to detonation and pre-ignition. Sometimes you hear mistaken terms like "pre-detonation". Detonation is one phenomenon that is abnormal combustion. Pre-ignition is another phenomenon that is abnormal combustion. The two, as we will talk about, are somewhat related but are two distinctly different phenomenon and can induce distinctly different failure modes.
Detonation is the spontaneous combustion of the end-gas (remaining fuel/air mixture) in the chamber. It always occurs after normal combustion is initiated by the spark plug. The initial combustion at the spark plug is followed by a normal combustion burn. For some reason, likely heat and pressure, the end gas in the chamber spontaneously combusts. The key point here is that detonation occurs after you have initiated the normal combustion with the spark plug.
Detonation causes three types of failure:
1. Mechanical damage (broken ring lands)
2. Abrasion (pitting of the piston crown)
3. Overheating (scuffed piston skirts due to excess heat input or high coolant temperatures)
Pre-ignition is defined as the ignition of the mixture prior to the spark plug firing. Anytime something causes the mixture in the chamber to ignite prior to the spark plug event it is classified as pre-ignition. The two are completely different and abnormal phenomenon.
Detonation is the spontaneous combustion of the end-gas (remaining fuel/air mixture) in the chamber. It always occurs after normal combustion is initiated by the spark plug. The initial combustion at the spark plug is followed by a normal combustion burn. For some reason, likely heat and pressure, the end gas in the chamber spontaneously combusts. The key point here is that detonation occurs after you have initiated the normal combustion with the spark plug.
Detonation causes three types of failure:
1. Mechanical damage (broken ring lands)
2. Abrasion (pitting of the piston crown)
3. Overheating (scuffed piston skirts due to excess heat input or high coolant temperatures)
Pre-ignition is defined as the ignition of the mixture prior to the spark plug firing. Anytime something causes the mixture in the chamber to ignite prior to the spark plug event it is classified as pre-ignition. The two are completely different and abnormal phenomenon.
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Bass Addict
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Pre-Detonation
Yep! .. And to think that this kind of dispute was once settled at dawn and at 25 paces or there abouts .......Billy Dee wrote:I'm confused. Is this whole thread due to someone who had the right idea, but used the wrong term? If so, I can only say... wow!
"If everyone is thinking alike, Someone isn't thinking" - George Patton