Where to Mount ECU After Rewiring

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1969VADart

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So as my engine harness rewire project proceeds, I have another question. Can you guys post some pics of where you mounted your ECU (orange box or whatever you have) in the engine bay? Previously, my ECU was mounted on the passenger side inner fender and the voltage regulator and ballast resistor where mounted on the drivers side of the car. However, the new wiring harness I am installing suggests that these three things need to be in more close proximity to one another. That means I am drilling a couple new holes and either (1) moving the ECU to the drivers side or (2) moving the voltage regulator and ballast resistor to the passenger side. Option 2 seems more tricky because I don't really have any firewall space available on that side of the car. I have seen some cars with the ECU mounted up on the side of the inner fender, like behind the washer jug. For reference I have posted a few pics of my current set up so people can get an idea of what I am dealing with.
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Would appreciate some ideas on this. Thanks.
 
Just a thought. Did this car originally come with electronic ignition? If you don't want it to show use some of the unused terminal block positions and mount the ECU under the dash.
 
Last one I had was my 65 Valiant. I put the voltage regulator and the ECU and ballast on the inside of the car, on the passenger's side just above the carpet on the inside of the firewall.
 
Just a thought. Did this car originally come with electronic ignition? If you don't want it to show use some of the unused terminal block positions and mount the ECU under the dash.

That is an interesting idea. I already have two wires for the neutral safety switch routed through one of the rubber plugs in the firewall (not how I set it up...somebody else did that for me, aaahhh!). Could probably take the same approach for the ECU.
 
As I recall there are two unused spaces on the drivers side of the terminal block for AC wires assuming you don't have AC. Another member posted a link to wire connectors in the past few weeks, they might be the correct ones to just pop into the terminal block?
 
That is an interesting idea. I already have two wires for the neutral safety switch routed through one of the rubber plugs in the firewall (not how I set it up...somebody else did that for me, aaahhh!). Could probably take the same approach for the ECU.
If you have 4 or 5 unused ports available in the OEM bulkhead connector. I personally don't want more troubleshooting, R&R, labor under the dash. I certainly wouldn't want the ballast resistor under the dash as described above. It gets extremely hot.
 
Maybe the electronics gurus will find this thread. IS having the shorest wires going to the dist the most important pat of the wiring for this or th wires that go to ballast,VR >????? Other than that keeping the ECU away from heat, good ground, (dry??),, is the other part.
 
I'm no wiring expert by any means, so take what I say with a grain of salt, but on the duster and dart I have mine mounted on the passenger side inner fender, I would just say to mount on a flat or close to flat surface with a good ground, the only issues i've ever ran into with these is making sure they are grounded well.
 
I really don't think proximity is the issue. The way I read it, the length of wire provided in the replacement harness is the issue.
 
While my car is not an original by any stretch, since it is a 68, I mounted mine to the Firewall, but inside, next to the heater box. I cut the wires to the Distributor, fed them through a grommeted hole under/behind the wiring harness right behind the dist., & soldered back together. No electronic ignition in that 68, nosiree.
 
Given the wiring layout of the new engine harness, the most logical place for the ECU is probably mounted vertical on the drivers side inner fender behind the washer bottle (like ProRac1 has). I don't want to have to be cutting and splicing on this new harness for any reason.
 
Here's what I did. This panel mounts under the dash and has the Mallory 6AL, Voltage regulator, starter relay, wiper motor resistor and 2 fuse blocks one switched, one unswitched.
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Given the wiring layout of the new engine harness, the most logical place for the ECU is probably mounted vertical on the drivers side inner fender behind the washer bottle (like ProRac1 has). I don't want to have to be cutting and splicing on this new harness for any reason.
I think that's a fine location especially if that's where the wiring harness wants it to be landed. I completely agree that no cutting and splicing is much better.
 
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