Rookie racers of gas powered RC cars used to find it difficult to tune the engine. They won’t have any trouble in starting the engine yet at the end of the run, it was overheated. Once gained experience, they can tune the engine in less than 5 minutes. Adjusting the optimal settings of the car will also be easier.

The Idle Screw

It is always advisable to start with the idle screw. Adjustments must be made so that the car will idle high when we initially dial the engine. Once the temperature of the engine is set, we can adjust the idle slowly to a point where it stalls. After this, we must turn it to one-forth or one-half based on the temperature. When our car stalls often, it is better to increase the idle. While we rectify several other tuning issues, it increasing the idle is only a temperature fix. It will also help us to keep the frustration levels down.

Low-Speed Needle.

If our carburetor has two needles, confusion may occur as to which needle it should be adjusted first. If it has only one needle then it is not a problem as we have to make adjustments only on that. When such type of confusion occurs, low speed needle should be adjusted first because once it is set, high-speed needle can be easily changed. We must always make sure that we keep the low speed needle on the rich side. This helps to keep the combustion chamber cool. Once adjustments have been made in low-speed needle, we should not adjust it again. When the engine stalls, we can tell whether it should be richer or leaner in a matter of just 30 to 60 seconds. The RC car should not get stuck or flame out when we apply a full throttle. It should pull off quickly from a standing start.

Nitro drift car

High-Speed Needle.

Once the adjustments in low-speed needle are done, we should get the power out of RC engine. This is possible with high-speed needle as it adjusts the air to fuel mixture of the engine. This is done at a RPM of about 40% or more. To get the first clue about the tune, it is important to monitor the trail of the smoke. Irrespective of the RPM, we need to have lot of smoke coming out of the engine. If we get a very low amount of smoke, then it means we are running too lean.

Hints, Tips and Tricks

• To lean out, turn the needle clockwise and to richen the mixture, turn it in anti-clockwise direction.
• High smoke emitting from the engine implies our tune is rich.
• After a run, reading the glow plug will tell us about our tune.
• Turning the engine on the rich side will extend its life.
• Temperature, pressure of the air and humidity influences the tune. So different settings are required on different days.