For any engine to reach its maximum potential, the fuel must burn efficiently. Running rich or lean is not good for performance, and in extreme cases it can be catastrophic. A rich engine is likely to ...

This is the basic Gunson CO tester. The 12-volt connections power the unit while the pulse pump draws exhaust gas into the analyzer. The unit is designed to measure CO exhaust percentages. Those ...

Tuning your engine with the aid of an air/fuel meter can really help you dial in your carburetor. But what numbers should you aim for? When people talk about the air/fuel ratio of their engine, do you ...