Perfect Power Online Manuals.


Support for your SMT8-FT Unit.


Here is a brief list of the features :

  • 1 Map to influence an analog signal : ANA1 MAP
  • 1 Map to influence an ignition signal : IGN MAP
  • 1 Map to tune injection length : FUEL MAP
  • 1 Map to influence an AFR/Lambda signal : AFR MAP
  • Two separate tune maps : Map Switching





An analog signal is intercepted via the AIN (pin 10/12) to AOUT (pin 10/12) connection. It is mapped via AMP/RPM, Engine Temperature, and Analog input for the purpose if altering an analog signal such as AMP at specific  engine conditions. The output signal can be limited (high and low) and offset aligned.





One ignition signal (CRANK) can be intercepted and mapped via AMP/RPM, Engine Temperature, and analog input for the purpose of retarding/advancing the ignition. Notice that the Ignition mapping affects ALL ignition signals (advance/retard). The output signal can be set to maximum advance and retard limits.





This large 16 x 24 point map modifies the injector length. Injection length can be shorter or longer. It has two side maps for engine temperature and Analog tuning.





A large 16 x 24 map allows for the precise AFR (Lambda) signal modification via the AIN (pin 4/12) to the AOUT (pin 10/12). The AFR is mapped via AMP/RPM and Engine Temperature. Notice that this map uses the same circuit as the analog modification, so both can't be used simultaneously.


Note : The narrow band circuit has been designed to work with the Bosch 4 wire narrow band lambda probe; the circuit is loaded with a 10K resistor, which could cause other sensors to operate outside of their normal voltage range.





The unit has an engine protection module, which can save the engine after a mishap has occurred. In response to an input going out of bounds it can :

  • Modify the analog output
  • Retard the ignition
  • Cut the ignition signal and/or cut the injection

For each of the above actions several limit parameters are available





The SMT8-FT has two complete maps. That is to say that you can switch between two different tuned maps while driving. It is possible to have one map for fuel-economy, and the other for performance. Or use the maps for different weather conditions. The maps can be switched from the hardware input (MAPSW). The parameters and calibration are not switched. The maps can be locked in to a fixed position from the PC for tuning and downloading. When the map switching is enabled in the set points the hard switching (pin 3/12) will no longer function.





The RPM range, AMP sensor and Engine Temperature sensor and scales can be calibrated and specified. The calibration is applicable to both tune maps A/B.





Help is available in various forms :

  • Right click on any item and a short explanation is available
  • This Technical Manual
  • The LetRipp Software User Guide
  • Some Windows Items are explained online