Jetting Honda GX 4T engine 4+

Nº1 jetting App for Honda GX & Clone 4T engines

This app provides, using temperature, altitude, humidity, atmospheric pressure and your engine configuration, a recommendation about optimal carburetor configuration (JETTING) and spark plug to use for karts with Honda GX & Clone 4 stroke engines, which use a Keihin BE carburetor (stock air filter or open K&N type air filter).

Valid for the following engine models with next Genuine Honda carbs:
• GX120 - stock .453" (11.5mm) carb or bored .524" carb
• GX160 - stock .520" carb, stock .570" carb from gx200, bored carbs from .615" to .670", stock .827" carb from gx390, bored gx390 carb .925"
• GX200 - stock .570" carb, bored carbs from .615" to .670", stock .827" carb from gx390, bored gx390 carb .925"
• GX270 - stock .670" carb, stock .827" carb from gx390, bored gx390 carb .925"
• GX340 - stock .827" carb from gx390, bored gx390 carb .925"
• GX390 - stock .827" carb, bored gx390 carb .925"

This app can obtain automatically the position and altitude to get the temperature, pressure and humidity from the nearest weather station thought internet. Internal barometer is used on supported devices for better precision. Application can run without GPS, WiFi and internet, in this case user has to enter weather data manually.

• For each carburetor configuration, the following values are given: main jet size, pilot jet size, float height, spark plug, spark plug gap
• Fine tuning for these values
• History of all your carburetor configurations
• Graphic display of fuel mix quality (Air/Flow Ratio or Lambda)
• Selectable fuel type (gasoline with or without ethanol, methanol, Racing fuels available, for example: VP C12, VP 110, VP MRX02, Sunoco, Methanol)
• Mix wizard to get the perfect mix ratio (fuel calculator)
• Carburetor ice warning
• Possibility of use automatic weather data or a portable weather station
• If you don't want to share your location, you can manually select any place in the world, the carburettor configs will be adapted for this place
• let you use different measure units: ºC y ºF for temperatures, meter and feet for altitude, liters, ml, gallons, oz for fuel, and mb, hPa, mmHg, inHg for pressures

The application contains four tabs, which are described next:

• Results: In this tab main jet size, pilot jet size, float height, spark plug, spark plug gap are shown. These data are calculated depending on the weather conditions and the engine configuration given in the next tabs.
This tab lets do a fine tuning adjustment for all this values to adapt to the concrete engine.
Besides this jetting information, the air density, density altitude, relative air density, SAE-dyno correction factor, station pressure, SAE- relative horsepower, volumetric content of oxygen, oxygen pressure are shown too.
On this tab, you can also share your settings with your colleagues, or add settings to your favorites.
You can also see in a graphic form the calculated ratio of air and fuel (lambda).

• History: This tab contains the history of all carburetor configs.

• Engine: You can configure in this screen the information about the engine, that is, engine model, air filter type, spark manufacturer, fuel type.

• Weather: In this tab, you can set the values for current temperature, pressure, altitude and humidity.
Also this tab allows to use the GPS to get the current position and altitude, and connect to an external service (you can choose one weather data source from several possible) to get the weather conditions of the nearest weather station (temperature, pressure and humidity).
In addition, this application can work with a pressure sensor built into the iPhone. You can see if it is available on your device and turn it on or off.
Also, on this tab, you can manually select any place in the world, the carburetor config will be adapted for this place.


If you have any doubt about using this App, please, contact us.