Installing an Emerald M3DK ECU with DIY 40mm Throttle Bodies

Modified 40DCOE Weber's
After a season using the Ford ECU & stock throttle body (which works great for general motoring but not for performance) I decided to install an Emerald M3DK (3D mapped) ECU and 40mm throttle bodies giving individual intake runners and throttle plate for each cylinder. This was partially based on the availability of a set of DIY throttle bodies for a very reasonable price. I traded a set of Wilwood brake pads to Arno Church (a Se7en racer from South Africa) for a pair of Weber 40DCOE sidedraftt carbs that had been machined down to perform as 40mm throttle bodies (TB's).

As received from Arno, these TB's were shorter than I had expected. I want to keep the intake track as long as possible to keep the torque curve high at intermediate RPM's (2000-5000). Originally I had planned on modifying the Burton Power intake manifold by adding bungs for the fuel injectors but to keep the intakes long, I decided to use part of the stock Ford Focus intake manifold.

I cut off the section that mounts to the engine and holds the injectors. This is about 1.25" long. I matched the ports on the Burton manifold and the Focus manifold to the intake ports on the head and sealed the focus manifold ports. Then the Focus manifold was sandwiched between the Burton manifold and the Zetec head and bolted together. I used Weber o-ring gaskets to mount the new DIY (Do It Yourself) TB's to the manifold - not because I wanted to isolate the TB's from the motor as is normally done with Webers, but just because they were handy.

I tried to purchase a top pull or bottom pull throttle linkage for the TB's but no one had anything that would work with these DIY TB's. So I build my own throttle cable mount using one from a Ford Focus. I also used the Focus throttle cable (see picture above).

With the TB's mounted I started on rewiring the car for the Emerald ECU. I removed the Ford ECU & wiring. The Emerald ECU is smaller than the Ford unit so I mounted it above the drivers left knee. The wiring goes from the Emerald, under the heater fan where a little over half of the wire exit the cabin to through the transmission tunnel to the engine compartment.

I added four relays for the Emerald system. A Run Relay; A Fuel Pump Relay; A Coolant Relay; An O2 Heater Relay and a 6-way fuse block (see wiring diagram). The theory is that the Emerald will turn on the Run Relay when the key is operated with makes energizes the fuse block. The Emerald then runs activates the Fuel (which turns off after 5 seconds if the engine does not start). With the engine running and the Fuel Pump Relay energized, the Coolant Relay and the O2 Heater Relay are powered and will activate under control of the Emerald ECU.

The Coolant Relay will turn on the radiator fan by shorting across the Birkin thermo switch. This is under ECU control, so I can decide at what temperature the fan turns on and off (90C on and 85C off) when the engine is running. If the engine is off, the fan can still run under control of the Birkin thermo switch (turns on at 100C).

The O2 Heater Relay is also controlled by the ECU. Any time the engine is one, the ECU can turn on the O2 Heater Relay. However, if the engine is not running, the ECU can not turn on the O2 Heater.

I also added a BARO sensor under the TB's. Where I live, in 30 minutes I can go from 4200 Feet above sea level to 9000ft above sea level and in 8-10 hours I can be at sea level. Hopefully the BARO sensor will keep everything at optimum operating efficiency regardless of Altitude.

I've also added a cigarette lighter that is mounted near the passenger's right knee.

Future additions will be a oil waring LED and a bright white shift light.

Currently, the engine starts and runs and idles at 980 RPM's. With the switch to the DIY TB's, I upgraded the injectors from the stock 18lb/hr (192cc/min) to 24lb/hr (256cc/min) Ford Performance injectors. The original injectors were good for about 135HP at an 85-90% duty cycle. The new injectors are good for 180HP at a 90% duty cycle.

Next project will be to get the mapping correct for this engine in this car with these TB's, injectors and the Birkin exhaust. Initially I will be using a map from a similar setup thanks to Keith Banthorpe.

More to come!!!

Installing a FORD Contour ECU, wiring harness, sensors:

1996 Focus ECU mounted on passenger side under scuttle
After a couple of conversations with Steven Lassovszky I decided to use the Ford ECU to control the Zetec motor - at least initially. Steve has posted wiring diagrams and instructions for using a 1996-1998(IIRC) for ECU's with the Focus engine. The files are posted on the Birkin Yahoo site: Birkin Yahoo site - ECU wiring for stock Ford ECU & Injectors file name:
(Note: "V11" refers to the version and may change)

After much thought I decided to retain the stock Ford wiring harness. If you are thinking about doing this, DON'T KEEP THE STOCK HARNESS. You will be hours ahead to start from scratch per Steve's documents.

Stock Focus harness being modified for the Birkin I tired to use as much as possible from the original 2001 Focus harness. I initially tried to use the 2001 Focus computer, but the PAT (Passive Anti-Thieft) features of this ECU were not easily defeated. Steve is currently looking into the possibilities of using this computer in the future.

I also used the stock harness for the injectors, unlike retaining the main harness, this was a good decision. This is the cable that runs from in front of the throttle body aft. This cable includes the cam position sensor and the Focus temperature sensor.

BTW, the stock Focus temp sensor is not totally compatible with the earlier computer systems but can be made to work with by adding a 2.7k resistor to the circuit. In the "wiring in progress" picture you can see the 2001 Focus combination MAF/IAT unit. This unit did not work with my 1996 computer. I don't know if it is a bad unit or just not compatible. So I used a 1996 IAT (Intake Air Temp) sensor that should be in the intake air stream but is currently located along side of the air cleaner and a 1996 MAF sensor (see finished picture).

Completed wiring with Ford harness and ECU In this picture you can see the new K&N style air filter and filter adaptor that connects to the Birkin Sport 90 degree intake. When trimmed this rubber unit will just clear the hood (or Bonnet).
All of the harness wires were feed into the central tunnel in protective black plastic wire shields. They then enter the car with the existing harness wires.

NOTE: This works well for my 2000 model Birkin with the fuse blocks inside, I don't know how well it would work on a later model.

Not shown in these photos are two relays and a secondary fuse block that I added under the scuttle. One relay controls the fuel pump using both the computer and the Focus roll over or inertia switch. This switch is mounted just on the scuttle just above the steering shaft within the reach of the driver (should it accidently open it can easily be switched back on). The second relay controls power to the computer and various sensors.

As you can see, I installed an Odyssey PC-680MJ battery. This is a sealed lead acid battery that is valve regulated. As a result there is no worry about spilled acid or acid fumes that will damage the car. I choose the MJ version that includes a metal jacket surrounding the battery for use in higher temperature areas. The battery only weighs a little over 14 pounds.

DriversideEngComp.jpg - 66473 Bytes From the drivers side you can see how clean the engine compartment is using the center tunnel for routing the wiring harness. In the future, I may replace the Ford ECU with an Emerald unit to allow a greater range of ignition and injection fine tuning.

From this side of the engine you can see the Birkin furnished coolant recovery bottle. You can also see the Focus throttle cable that was shortened for use in the Birkin. The Birkin throttle assembly allows you to adjust a throttle stop at the throttle pedal. I does not allow you to adjust a closed stop. I added a closed throttle stop and adjusted the full throttle stop to allow the throttle to fully open the throttle body without putting excessive tension on the throttle cable. (See engine photos for the throttle stop).

Hiding in the lower center of the picture you can just see the white and green O2 sensor connection.


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