Just wondering if an automotive rpm gauge will work for a prop trial. My rpm gauge is no good and looking for an alternative till I get a new one. Thanks .
Be mindful that some automotive tachs have a selectable switch on the back to condition the input for the correct indication with regards to the number of cylinders, and this is based on a four stroke engine, not two. If set for a four cylinder, your reading would likely be twice the actual until the instrument was set for an eight cylinder.
