SMT8-FT TECHNICAL MANUAL

Perfect Power Online Manuals.

 

Support for your SMT8-FT Unit.

KEYWORDS

ECU

The computer box, which is controlling the engine's operation

 

MAPPING

A process by which, a signal is manipulated via the various tuning maps.

 

INTERCEPTING

A wire is cut, and the two ends are routed through the SMT8-FT for the purpose of changing the signal.

 

TEE IN

A wire from the SMT8-FT is joined to the standard wiring loom. The signal is only read, and no modifications take place.

 

LAMBDA, OXYGEN, AFR

A lambda probe, oxygen probe, or AFR sensor all measure the oxygen content in the exhaust pipe. At lambda 1.00 the AFR = 14.7 and a narrow band sensor generates a  voltage between 0.2 and 0.8 Volts.

 

CHIPPING

Traditionally this applies to changing the "chip" of the ECU to provide better  performance. When ECU's started to control the engine it meant changing an  EEPROM. The term now also applies to adding a SMT8-FT to the car, without changing any chips or EEPROMS. The SMT8-FT has the advantage over chipping because of the online tune and the re-tune capability.

 

MAF

Mass Air Flow sensor. It could be a device with a flap or a solid-state "hot wire" sensor. It generates basically an analog output voltage, which increases with higher airflow. Some devices compensate for air temperature (density).

 

MAP

Manifold Absolute Pressure. It is a solid-state device with 3 wires and provides an analog output  voltage, which increases as the manifold pressure increases. Since it measures the absolute pressure the output voltage decreases at idle. We don't  like this term because is also applies to a tuning map.

 

AMP

Absolute Manifold Pressure. The same thing as a MAP. We like this term because it can't be confused with a tuning map.

 

MAP SWITCHING

All of our units have two tuning maps, which can be switched while driving. There are THREE possible map-switching scenarios.

 

PICKUP

It is a sensor, which "picks up" an engine measurement like temperature or crank angle position. The sensor can be a Hall Effect (square wave) or magnetic (sine wave)

 

FEED-THRU

A method where a wire is cut and routed through the SMT8-FT for the purpose of modifying the electrical signal.

 

BALANCED INPUT

Refers to a magnetic pickup (CRANK/CAM position) where the pickup coil is isolated from ground. If a balanced input is tested with a scope, then both wires have an opposing signal on it. The SMT8-FT has balanced inputs on all three trigger inputs.

 

MAP SWITCH INPUT

A switch input when not used defaults to MAP=A

 

DEFLECTION (THROTTLE/AMP) INPUT

It is a tee-in signal in the range from 0-5 Volts. Normally a low voltage refers to a closed throttle or no load. The SMT8-FT uses an AMP signal for deflection, but any other signal can be used on the AMPIN pin 11-12.