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Pro Flo 4 ECU mounting

JKCuda

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I’m arguing with myself as to where I want to mount this thing. The harness is kind of a pain in the ass to work with being wrapped in a plastic like sleeve instead of something braided loom like I would’ve done. The connectors are massive so if I mount in the cabin I’d 100% have to drill a large hole in the firewall, something I don’t know that I want to do.

Anyone else installed one on an ebody and have pics or suggestions? I just can’t make up my mind.
 

rmchrgr

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From the pictures I've seen of it, the Pro Flo ECU and harness appears similar to the Holley EFI stuff. I can't see how you'd want the entire harness in the engine bay if it's even possible. I have a Holley Terminator X and mocking it up I learned pretty quick there is not a lot of room to mount an aftermarket ECU and harness under an E body dash easily and/or cleanly. This is especially true with an A/C heater box.

I thought about putting the ECU under the driver seat or the console. The seats are really low in these cars though and figuring out how to route the wiring out from that area would be difficult. Not sure if there would be enough room under the console, might be worth a look. Or, if you don't care about it being out in the open it could be mounted in the passenger side foot well like a race car wiring/ignition panel. I don't think there's enough room behind the kick panels.

Right now I'm looking at mounting the Holley ECU behind the rear seat or in the forward part of the trunk and running the harness up to the front in the driver's side wiring trough. I spent the extra coin on an unterminated, 15' "flying lead" wiring harness because I learned from two previous Holley EFI installs the supplied harness is useless. My Challenger is completely apart right now though so it's easy to mock that up but it would certainly be a much more difficult prospect with the interior still in.

If you don't like the provided sleeving you can always discard it and use the kind you prefer. I like the split loom style and use non-adhesive tape and/or zip ties to keep it closed. You can get it in bulk from most of the electrical supply places.

In regards to the firewall - at some point you'll need to get whatever wiring is necessary into the engine bay. At a minimum you'd have to de-pin the connectors to even be able to route the wiring through smaller holes or cut it and use bulkhead connectors to pass them through. Maybe you can separate things into sub harnesses so you can pass smaller bundles through a couple different points.

Sometimes you gotta make stuff work.
 

JKCuda

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Appreciate the detailed response. All things I’ve considered…. I really like the kit but the wiring harness leaves a lot to be desired. I rewired the car with the American auto wire harness and it was a dream to work with. This thing is….not that. I may look at depinning the harness to pass it through but I haven’t looked at the connectors close enough yet to see if that is a viable solution or not. Unfortunately based on what I’ve seen from other cars, chevys and fords, I may end up mounting the ECU on the pass side firewall and just cleaning up the wiring in the engine bay…. It’s a shame they put such a nice kit together and didn’t think the wiring harness through very well.
 

scar426

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Appreciate the detailed response. All things I’ve considered…. I really like the kit but the wiring harness leaves a lot to be desired. I rewired the car with the American auto wire harness and it was a dream to work with. This thing is….not that. I may look at depinning the harness to pass it through but I haven’t looked at the connectors close enough yet to see if that is a viable solution or not. Unfortunately based on what I’ve seen from other cars, chevys and fords, I may end up mounting the ECU on the pass side firewall and just cleaning up the wiring in the engine bay…. It’s a shame they put such a nice kit together and didn’t think the wiring harness through very well.
MOPAR harness is the same. had to mount pass firewall in engine bay. I routed the "inside" harness through a smallish hole i drilled in the inner fender well, less noticeable and came in high on the firewall inside the cabin. Good luck.
 

rmchrgr

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I've used AAW kits myself and find their stuff lacking as well. Both times I've used them I ended up removing a bunch of extra wire an found myself re-doing large portions of the main harness. And using GM connectors in Chrysler harnesses is less than ideal. The TXL wiring is decent though and their kits are fairly complete so you take the good with the bad.

Honestly, I probably wouldn't even consider any other brand of retro EFI these days besides Holley. The Edelbrock stuff does not enjoy the same level of support or have the same amount of peripheral products (if any) available for it. Yeah, most of those trinkets are designed to separate you from your money but I'd rather pay a bit more to make life easier over wasting time trying to re-engineer something.
 

JKCuda

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I've used AAW kits myself and find their stuff lacking as well. Both times I've used them I ended up removing a bunch of extra wire an found myself re-doing large portions of the main harness. And using GM connectors in Chrysler harnesses is less than ideal. The TXL wiring is decent though and their kits are fairly complete so you take the good with the bad.

Honestly, I probably wouldn't even consider any other brand of retro EFI these days besides Holley. The Edelbrock stuff does not enjoy the same level of support or have the same amount of peripheral products (if any) available for it. Yeah, most of those trinkets are designed to separate you from your money but I'd rather pay a bit more to make life easier over wasting time trying to re-engineer something.
The only issue I had with AAW was mating it to the GM ignition switch on my flaming river column but one quick call to their tech support solved that. I read so many posts about Holley issues with heat soak and such while cruising, and honestly I wanted something different than what everyone else was running so I went with the edelbrock. I’ll figure it out, just not thrilled with the harness length and the ability to customize it without hacking it up.
 

JKCuda

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MOPAR harness is the same. had to mount pass firewall in engine bay. I routed the "inside" harness through a smallish hole i drilled in the inner fender well, less noticeable and came in high on the firewall inside the cabin. Good luck.
I may look into this. I passed my wideband harness through the large hole by the brake booster but no chance these edelbrock connectors fit through that.

In all honesty though, I’m probably leaning towards mounting it on the pass side firewall and just cleaning up the wiring as best I can. It’s not a show car, I built it to drive.
 
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