Tuned Exhaust Systems & Procedures

The PFS tuned-exhaust system on the club's 172s will provide a 20+ horsepower boost and a reduction in fuel consumption, but only if you use the correct operating procedures.

Immediately upon engine start, lean the mixture. Remember you cannot harm the engine on the ground by leaning. The engine will stop before any damage could occur. So remember to really lean during all, repeat all, ground operations.

Take off in the normal manner. Mixture rich just before advancing the throttle. Keep throttle full open through out climb. Red line is 2700 and the engine is capable of maintaining sustained flight at that red line limit.

You can begin leaning on climb when you pass through 2500/3000 feet. When you reach cruise altitude, level off and maintain a minimum of 2450 RPM on the tach meter. The manufacturer says even running at full throttle won't hurt and will result in greater performance gains. These aircraft do not have an Exhaust Gas Temperature (EGT)or Cylinder Head Temperature (CHT) gauge. Therefore, you MUST LEAN until the engine gets rough then advance the mixture slowly until the engine is running smoothly (warn your passengers first...).

Using the system outlined above will enable us to get the most out of the tuned exhaust system. You should notice an immediate improvement in climb performance. Additionally, IF you lean properly you could obtain a fuel burn reduction of 2 to 3 GPH.