Discussion and questions related to the course EFI Wiring Fundamentals
What is the best practice re end of harness connectors -
1 build a harness with specific connectors for each use case , e.g. a mix of metri-pack, weather-pack, packard , USCAR, mini-timer etc equired for each sensor / actuator
2 standardise on something like DT/DTM for all end of harness connectors and then use an adapter for each sensor / actuator.
I am not a huge fan of the second option as it introduces an extra failure point and also adds to the cost but when you look at things like pressure sensors with a Packard style connector or injectors such as the ID injectors that use a USCAR connector, if you decide down the path to change brand / version of injector or sensor all you need to do is change the adapter however if you build the harness with specific cnnectors you would need to in most cases cut off the existing pins, connector and boot and re-term with a new connector (if you have enough wire to do that).
WRT Injectors, it would be pretty safe to term with MiniTimer and then adapt as required and then pretty much everything else with DTM and adapt as required.
OR, (3) would you build the harness first time with the correct connectors to suit all sensors / actuators etc and then if you need to change something down the track use an adapter?
G'day Ben. Really great question.
The second method you've mentioned doesn't work out well in my experience, as it essentially doubles the number of connectors you need, and makes things bulky and messy in appearance, I wouldn't recommend it.
Most of the time I will build the harness with the specific connectors it requires to connect to the actuators and sensors in place, as usually the build will be fairly finalised by this stage.
However, another great way to go is to use sub-harnesses. Your main harness can have a single connector on it, say a DTM-12 pin for an 8 cylinder, that is the 'injector connector'. It could have a couple of power supply pins and the rest wired back to the injector outputs of the ECU. Then you build a sub-harness which connects to this, and then to your actual injectors. If you change the injectors out later on, you only need to rebuild the sub-harness. Or, because the sub harness can now most likely be easily removed from the vehicle, it can be modified much more easily out on the bench to suit the new injectors.
Hope that helps :-).
Had not considered the sub-loom , that should do the trick.
It is mainly the injectors and map sensor that I am cocerned about. I have spent last couple of weeks getting the harness documented (man this takes some time) and it has been a great process not just from the point of view of mapping out all the connections but it also forces you to consider a whole bunch of things related to the engine and chassis.
As this is a complete ground up build I am working on, I dont have any existing constraints to work to and can do everything fresh but need to keep in line with some category regultions that i must comply with. One of the restrictions is the use of turbo restrictor which has dictated a high comp build with lower boost. After considering all of the options, I have decided to go with a delco 3 bar map sensor as it will cover the boost range I am looking at nicely and uses a weatherpack connector. The thought that crossed my min dis that at some point, Imay change category which may allow me to run higher boost, at which point I would change to a Honywell 4-5 bar map sensor which uses a different connector.
The same applies with injectors, Iam looking at going with ID1300x's at the mo but down the track with extra boost may change to a bosch or something else which will most likely hav a different onnector to the ID' which seem pretty unique in thier use of USCAR.
Most of the other ecu sensors will remain the same over time, water temp, oil pres / temp etc are unlikly to ever be changed but as i worked through my cabling list (with 29 sensors, 4 x injectors, 4 x ignition, ecu, dbw controller dash etc) i realised there is some potential for connector changes down the track should anything need to be changed.
Looks like sub-loom will be the way to go.
Sounds like a fairly full on build! Make sure you share some details as you progress :-).