What is the SAFC?

What is the SAFC?


Today we’ll be talking about the Apexi Super AFC, and How to Setup the Apexi Super AFC as well as it’s many many variations. We receive a lot of requests and questions about this remarkable tuning device, so we’re taking this time to show you exactly how to setup your Super AFC.

Before we begin the How to Setup your SAFC part of our Guide however, let’s review the SAFC fuel tuning computer and what it does for your vehicle.

What is the SAFC?

When using a piggyback like a AFC.
When using a piggyback like a AFC.

The SUPER AFC II is a fuel adjustment controller in which the airflow sensor signal or the pressure sensor signal can be modified in a 12 point RPM range by 1% increments to increase/decrease fuel in a range of +50% to –50%. The RPM to be corrected can be optionally set in 200 RPM increments, and corrections can be made according to throttle opening amounts.

In a turbo equipped vehicle with a hot wire type airflow meter, this controller provides a preventive function for engine stall due to blow-back during throttle return. The controller, which includes a knocking meter, allows the monitoring of knock
levels check keeping the engine under its optimum condition at all times.


VFD Monitor

The futuristic front face of this unit uses the large screen, high-brightness and easy to read VFD (Vacuum Fluorescent Display)
Use of the dot-matrix large screen monitor allows the displaying several types of information simultaneously. Display variations are not limited to only numeric value display, but also graph display, analog display, and other various displays are shown. This allows the driver to recognize important information in an instant.

thin FORM FACTOR and single button

A thin case of 52 mm(L) x 126 mm(W) x 18 mm (D) (Minimum) has been achieved by optimization of the circuit board and case design. The product can be easily installed on the steering column or dash board. Since there is no separate unit besides the main unit, it is not necessary to secure a place for installing any separate unit. Using a
4-direction switch with a center pushbutton and a rotary switch gets rid of the button- to-button distance and permits quick operations, thereby providing efficient operation of the unit.


Battery-less memory

With the use of the EEPROM, the initial setup data is not lost unless initialization is performed, even if the power supply is turned off or the vehicle battery is disconnected. The setting data, such as peak value and correction value, is never lost. Accordingly, if the vehicle battery is disconnected for service inspection, initial setup and settings do not need to be performed again and the data history is not lost.

Two fuel tables for different throttle ranges


Two patterns of setting data including air correction factor, throttle opening, air  correction engine revolution speed, deceleration air upper limit, etc, can be stored in the memory. There are two files that can be stored in the memory. The setting data  can be selected in an instant according to each driving stage such as circuit driving, town driving, and winding driving.

When driving on the same stage, two patterns of   setting data can be compared. These patterns of setting data can be used for various  purposes.

Setting disable function by password


If the setting data or initial set points are changed by disoperation or mischief, the car condition may be deteriorated, or in the worst case, the engine may be damaged. In   the SAFC II, when the user sets a password optionally, changing the setting data or   initial setup items is disabled.

Warning function to make hazard known

It is possible to set warning values for the airflow using ratio, suction tube pressure,   Karman swirl sensor frequency, knocking, and engine revolution speed.

When each item is set, the car condition can be precisely judged. The setting for the   engine speed can also be used as a shift timing point.



Spontaneous ignition is caused by the heat and pressure of mixed air in the burning   portion of non-combustion gas which is far from the plug and the heat of combustion

chamber wall, so that the gas in the whole combustion chamber generates high-   pressure waves momentarily. In this phenomenon, strong metallic noise is output from   the engine unlike car knocking by which the car body becomes jerky, with the result   that the valve is damaged and the piston is seized, thereby giving fatal damage to theengine.

As countermeasures, fuel adjustment, ignition timing adjustment, compression ratio  adjustment, improvement of intake-side squish area, use of mirror type combustion  room wall, and profile improvement of the exhaust-side cam shaft can be mentioned.

Now that we’ve covered the common question of “what is the SAFC” we can move onto Setting up your SAFC in our How To Setup your SAFC Guide. Click on the green arrow for part 2 of our SAFC Guide.

IPC OBDII Trouble Codes
How To Setup your AFC