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S40i ECU – Ignition Only




Product overview


Maintaining the highest manufacturing quality and reliability of more sophisticated ECUs in the S series range it provides a lower priced solution for a wide range of applications.

The primary aim of the S40i is to provide an economic ECU for relatively simple wasted spark four cylinder engines using carburetor fuelling systems.

Advanced features and system flexibility, however, are in no way sacrificed to this aim.

Product features

Engine Configuration

20,000 rpm capability Flexible and easily adapted to different OEM and custom crank sensor arrangements. Genuine four and two stroke support. Wasted spark or distributor. User controlled fan activation. Sensors can be calibrated individually with a lot of preset options supplied. Flexible Tacho Output Soft and hard rev limits

Main Ignition Functions

Air, coolant and manifold pressure compensation maps. RPM and load breakpoints can be calibrated by the user. Throttle or MAP as load. All maps with one or two dimensional with interpolation as required.

Turbo Control Functions

Open or closed loop turbo pressure control via PWM valve. Modify target turbo pressure by gear selected. Modify target turbo pressure by vehicle speed. Active base PWM map for easy calibration.

Idle Control Functions Open or closed loop idle speed control via PWM valve. Closed loop idle target speed temperature dependant. Active base PWM map for easy calibration.

Flexible Input/Output Three uncommitted input tables which use 0 - 5 volt inputs or any input the S40 knows already, linked to fuel and advance modifiers and a PWM output.

Launch Control Fully flexible first gear launch capability. Extensively tunable to individual vehicles.

Full Throttle Gear Shift Cut Shift cut capability with 1ms resolution, variable for each gear with full switch de-bounce capability.

Voltage Compensation Tables

User configurable voltage compensation tables for coil on time (dwell time).

Diagnostics and Test Features Full sensor diagnostics and fault recording. Extensive engine run time recording at different load and speed conditions. Ability to exercise coils without engine running for fault finding.

Firmware The ECU firmware is flash upgradeable via the serial port with a special cable and software. Current firmware and software published on www.dtafast.co.uk.

CAN PC Communications The ECU can communicate with the PC via our USB -> CAN converter. This solves the problem of unreliable USB -> RS232 converters.

Other Features Sealed Latching Connectors Size 115 x 100 x 41 mm Weight 268 gm All outputs protected against over temperature and over current Inputs protected against severe wiring mistakes and accidents Reverse battery protection Alternator load dump protection

Inputs and Outputs Inputs Crank Shaft (Magnetic Only) Throttle Position Coolant Temperature Air Temperature Manifold / Barometric Pressure Lambda Oil Pressure Fuel Pressure Oil Temperature Battery Volts 3 x User Defined Analogue (Shared Use) Launch Switch Shift Cut Undriven Wheel Speed

Outputs 2 x Coil Drivers Tacho Fuel Pump Relay Fan/Aux 2/Turbo Pressure Valve (Shared Use) Idle Valve Shift Light