Jetting Tips: Weather and Elevation
Product Description
Ambient Air Temperature / Humidity
• As the air temperature or humidity decreases, the air density increases, requiring a richer air-fuel mixture. If the air-fuel mixture is not properly richened, and the mixture is too lean, higher cylinder pressures / temperatures, knocking, and the subsequent increase in the spark plug tip temperatures can result.
• As the air temperature or humidity increases, the air density decreases, requiring a leaner air-fuel mixture. If the air-fuel mixture is too rich, decreased performance and/or carbon fouling can result. Barometric Pressure / Altitude
• Air (atmospheric) pressure and cylinder pressure decrease as altitude increases. As a result, spark plug tip temperature will also decrease.
• Fouling can occur more easily if the air-fuel mixture is not adjusted to compensate for the altitude. Higher altitude = less air = less fuel.
• As the air temperature or humidity decreases, the air density increases, requiring a richer air-fuel mixture. If the air-fuel mixture is not properly richened, and the mixture is too lean, higher cylinder pressures / temperatures, knocking, and the subsequent increase in the spark plug tip temperatures can result.
• As the air temperature or humidity increases, the air density decreases, requiring a leaner air-fuel mixture. If the air-fuel mixture is too rich, decreased performance and/or carbon fouling can result. Barometric Pressure / Altitude
• Air (atmospheric) pressure and cylinder pressure decrease as altitude increases. As a result, spark plug tip temperature will also decrease.
• Fouling can occur more easily if the air-fuel mixture is not adjusted to compensate for the altitude. Higher altitude = less air = less fuel.
