WMS / SDS Programmable Engine Management for Fords
Take control of your engine with our stand alone Programmable Engine Management System. Developed by Western Motorsports and Simple Digital Systems to replace the Ford EEC fuel injection computer. Our DFI allows you to program all parameters for fuel and ignition to tune for maximum power from any engine combination.
The WMS / SDS is available as a plug in system for the Ford EEC equipped 5.0, 351W, 460, and 2.3. Of course most systems are used in 86-95 Mustangs but 86-95 Ford truck owners find our SDS system a far more powerful alternative to mass air conversions. The WMS / SDS system is also available with an engine harness that can be used in street rods, race cars and other Ford engines. Our newest system is available for the 4.6 and 5.4 modular powered Mustangs as a plug in system or with a harness for modular engine swaps.
Features of the SDS Injection System
- Plug and play! The easiest engine management system to install and program on the market today. Typically in about two hours the system is up and running.
- Stand alone digital injection system that replaces the Ford EEC computer taking control of all fuel injection and ignition functions
- New datalogging of Air/Fuel ratio from narrow or wideband O2 sensor in the handheld programmer for easy tuning. Setup to log our WMS Wideband and other brands that have a 0-5V output.
- Supercharger and Turbo compatible up to 30lbs boost. Handles fuel enrichment, timing retard, boost limit, rev limit and more.
- No expensive laptop or complex software is required. Our handheld programmer handles full sensor diagnostics and programming in real time with easy to understanding tuning.
- Does not require a restrictive mass air flow sensor that must be calibrated to different injector sizes. If you change injectors or make changes in the engine, you can program the system to take advantage of the changes through the user friendly SDS programmer.
- Comes with pre-programmed fuel and timing curves to allow initial start up. Once your engine is running, tuning is easy to complete.
- 1 Year warranty and complete technical support.
- Excellent driveability for street, drag or road race engines. System flexibility means your race car can be tamed for street duty. Simple installation for 5.0 & 4.6 EFI engine swaps in early Mustangs, Cobras and Rods.
Our newest version of SDS software now includes datalogging for a Wideband O2 sensor. This great new feature captures the air/fuel ratio for each RPM and stores it in memory. AFR is then displayed in the programmer as shown, window, making tuning very eash. If you see that the AFR is too rich or lean in a range, then you can change that rpm fuel value.

SDS Pricing - click for a full list of systems, parts and pricing
What's Included with SDS?
- SDS Electronic Control Unit
- SDS Programmer
- Injector drivers
- Lean / Rich controller
- MAP sensor for naturally aspirated or blown applications
- Complete wiring harness - either a plug in harness or full harness system
- Installation and tuning manual
Everything you need to install and program the SDS on a Ford EEC controlled engine is included with the exception of an ignition box. Distributor engines (5.0, 351W, 460, 2.3) use a basic MSD 6A or similar, 4.6 / 5.4 engines use the MSD DIS4 ignition.
On plug in systems the factory Ford engine harness, water temperature, air temperature and throttle position sensors are retained. The system uses the Ford TFI distributor trigger and the SDS controls the ignition box. Only the basic MSD6A or Crane Hi-6 is required as the SDS system controls ignition retard and rev limiters. The SDS will control both factory and aftermarket fuel pumps.
The system was engineered so that installation can be easily handled by a first time installer. You do not need to be a fuel injection specialist to install or tune our system. Basically the EEC computer is removed and our harness plugs into the EEC port in the Ford engine harness. All the system components are connected with the supplied harness, a wire is connected to the ignition box and that's it - the wiring is complete! Installation typically takes less than two hours.
SDS System Adjustability
All Parameters controlling fuel injection and timing are adjustable using the SDS programmer unit including:
- Fuel curve for RPM 250 rpm increments from 500 to 9750 rpm
- Fuel Curve for Manifold Pressure 64 points from 28" vacuum to +.8 lbs
- Fuel Curve for Boost 64 points from 28" vacuum to +30lbs boost
- Fuel Curve for Air temp 64 points from -58c to +392c
- Fuel Curve for Water temp 32 points from -32c to +212c
- Fuel curve for Cold start 32 points from -32c to +212c
- Accelerator pump function 3 adjustments
- Closed loop operation on / off at RPM and MAP points
- Ignition curve for RPM 250 rpm increments from 500 to 9750 rpm
- Ignition retard for Boost 64 points from 28" vacuum to +30lbs boost
- Ignition advance under cruise for better mileage and drivability.
- Rev protection 250 rpm increments from 500 to 9750 rpm
- Boost protection up to 30lbs boost
- Knock sensor sensitivity and timing retard
- Radiator electric fan on / off temperatures
- Fast idle on / off temperatures
Once the system is programmed the controller can be removed and no further tuning is necessary until changes are made to the engine. The system automatically compensates for any changes in temperature, air density and altitude.
Programming the SDS Digital Injection System
The SDS LCD Programmer is one key feature that makes our system better than other DFI systems. You save hundreds of dollars right off the bat because our system does not require a laptop or its programming software. All programming functions are performed through the handheld programmer shown below. You can select a value you wish to change with the flick of a button and then change that value with another button - done! No confusing menus to fight with, no programs to learn - no other DFI is faster and easier to program than SDS.

Gauge Mode
Shown above is Gauge 1 which displays MP (Manifold Pressure), RPM, ET (Engine Temp) and AT (Air Temp) in real time. This allows you to monitor essential sensor inputs and make any changes where the engine is unhappy. Gauge 2 displays position of the Mixture Knob, Duty Cycle of the injectors and Timing degrees
Fuel Curves
There are 5 separate fuel curves that SDS uses: RPM, Manifold Pressure, Air Temp, Water Temp and Cold Start. Each fuel curve can be fine tuned to your engine combination for maximum power and driveability. To make a change simply select the curve and value you want to change using the <> buttons . Shown above is the RPM curve at 2750 rpm, the fuel value is 83. To add more fuel press +1 to add a little or +10 to add a lot. To lessen the fuel delivery press -1 or -10, its that easy to program!
Accelerator Pump
The accelerator pump function is used to provide crisp throttle response when the accelerator pedal is depressed. A fuel value for low and high rpm can be adjusted in the programmer to fine tune the accelerator.
Closed Loop Operation
The system uses your factory oxygen sensors in closed loop operation for excellent mileage when highway cruising. This is programmed by setting a 'IN' closed loop value (low rpm or high manifold vacuum) and an 'OUT' closed loop value (high rpm or low manifold vacuum)
Ignition Curves
Ignition curves can be set at 250 rpm intervals, starting with base timing at idle and working up to maximum advance at higher rpm. Changing the ignition curve is just like changing the fuel curve, select the value you want to change and press the +1 or -1 button. There is also an ignition retard under boost function that will pull back timing the amount you desire for a given amount of boost.
SDS Pricing - click for a full list of systems, parts and pricing







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