Boost

For reference.

Hi Guys,

I’ve had an enquiry as to how I’ve used my E-manage Blue/Ultimate as an Electronic Boost Controller. The E-manage should be able to control as well as any EBC, but will most likely require a little bit of tweaking in order to get it working perfectly. There is a little bit more involvement then some stand alone EBC’s, but you have the benefit of accurate and possibly finer control along with the opportunity to control the amount of boost at different RPM and how the boost comes ‘on’

The E-manage units have an ‘Additional Injector Map’ which is available for driving one or two additional injectors to provide more fuel to the engine. Not many people employ this as a function so it leaves the possibility for the map to be used for another function – in this case as an EBC. You can use a small circuit modify the output to become a switched ON-OFF output to control other devices also, but I won’t be going in to that here.

In order to use this output as an EBC, you will also need a ‘duty’ rated 3-port boost control solenoid and tube, some wire, and a fused 12volt ignition feed.

Boost Solenoid Connection: – Most aftermarket 3-port solenoid valves will be suitable, MAC, Apexi, HKS, Haltec etc, so long as they have a coil resistance of 15 OHMS and greater. Any less then 15 OHMS will require a drop down resistor in order to not damage the injector drivers inside the E-manage.

Connect the NO port on the solenoid valve to the compressor housing feed and the COM port to the Wastegate actuator. The NC port should vent to atmo.

We do it like this so when the solenoid is unpowered or if it electrically fails, the wastegate will see boost pressure and failsafe back to STD boost.

Electrical Connection and Jumper Settings: – We will be using one of the Additional Injector Output wires to feed one side of the Boost Solenoid (the negative ‘-ve’ or black if your wires are marked). The other side of the Solenoid is connected to a fused ignition switched 12 volt source. Using a 5-10A fuse here will be sufficient and protect the wiring and E-manage.

Internally in the E-manage you will also need to connect some ‘Jumpers’. JP5 and JP6 will need to be changed from ‘OPEN’ to Closed, so the little black jumpers are joining pins 1 and 2.

Map Adjustment: – Once the boost set-point in chosen we can set up a base map in order to fine tune the boost control.

The settings will depend on how you have the Boost Solenoid plumbed in and also, what you want your boost set-point to be.

The Additional Injector Map can be referenced to the factory MAP sensor or the GReddy 3-Bar unit against RPM. You can adjust the axis to suit your points having minimal space between no boost and smaller increments around your set-point boost you will be able to control the boost more accurately. For each of the ‘cells’ you can set a figure between 0-100% which is the percentage amount that the wastegate will see of the compressor outlet pressure. The frequency (sometimes called ‘gain’ on other EBC’s) of the switching is dependant on RPM in this case and increases as the RPM increases.

With the Set point chosen, in my case above, you can see it’s set to start to open at 140kPa (20.3psi) and reduces the duty down to 0% at 150kPa (21.7psi). What this means is that up until 20.3psi the solenoid is stopping any boost being fed to the wastegate actuator, but starts to open after this and if the boost still climbs to 21.7psi the actuator is seeing full boost pressure from the compressor housing and should drop the boost pressure back down as the wastegate bleeds off exhaust around the turbo’s. Ideally with the correct settings it is possible to get the boost to climb rapidly and then sit steadily between the 20.3psi and 21.7psi set points. I have not tried these with the standard turbo’s yet and do not suggest you copy the figures in my map, they are just to show how I went about setting my points.

You will also note that I have the bottom two rows set at 0%, this is to stop the annoying click of the solenoid when idling and normal driving where you are not boosting. You could quiet comfortably set these even higher then I have and instead of having a large block of 100% cells, could expand the axis around the boost set-point for finer resolution in this area.

You may also note I have some 95% cells at 3500/3600RPM this is to catch the spike that might occur with the boost ramping hard when the second turbo comes on-line.

I’d also suggest changing the columns with the boost control starting at approx 3200RPM with the STD twins as this is the ECU changeover point

In all a pretty powerful EBC in that you can set different boost for different RPM etc and it should work great once you’ve done some basic tweaking re duty cycles etc it will control the boost perfectly.

Cheers

Ben

OP: http://www.jzs147.com.au/forum/viewtopic.php?t=5675

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