• Overview
  • Lead separators


The NTK Air-Fuel Ratio Monitor is a tool to measure the air-fuel ratio (AFR) produced by carbureted and fuel-injected engines.

Its measurement range is from 9.00 to 20.00 air-fuel ratio for unleaded fuels, equating to (0.62 to 1.37 Lambda) and is also compatible with fuels other than unleaded.

The AFRM’s display is designed to show air-fuel ratio values based on an unleaded scale with 14.7:1 AFR as the stoichiometric ratio. The monitor will display on an unleaded scale even though the fuel used may have different properties (stoichiometry for methanol is approximately 6.5:1).

The same principle applies to other fuels such as ethanol, propane, CNG, LPG etc. The display will simply read on an unleaded scale. As long as the engine runs between the range of 9.00:1 – 20.00:1 AFR (or 0.62 to 1.37 Lambda), the AFRM will work with almost any fuel type.