ECM placement?
Thread Starter
Pro
Joined: Jan 2016
Posts: 502
Likes: 103
From: Reno Nevada
ECM placement?
I am getting started on my whole car rewire and need to locate my Holley Terminator ECM. I have vintage Air installed taking up the entire right interior of the car and the Terminator wiring harness is not quite long enough to place the ECM in the jack tray (where I wanted it), so next placement is behind the right fender inside the engine compartment under the coolant overflow reservoir. Figured I would build a metal tray to put it inside with the wires exposed downward to protect it from heat, etc. But it will be exposed to the weather a bit.
Holley says it is fine outside, but checking to see where people are placing their ECM's and if anyone has had any weather related problems with any of them in an engine compartment.
Thanks in advance.
Holley says it is fine outside, but checking to see where people are placing their ECM's and if anyone has had any weather related problems with any of them in an engine compartment.
Thanks in advance.
Melting Slicks
Joined: Apr 2001
Posts: 2,030
Likes: 363
From: Lubbock Texas
I'm putting the ECM for my Edelbrock Pro-Flo 4 EFI system and the Compushift controller for my 4L60E transmission in the right fender area between the back of the fender and the firewall. I'm being **** about it and plan to install both in weather tight enclosures from Polycase and then place a heat shield in front of the installation. Might be overkill but Compushift says that even though they allow the controller in the engine compartment, they prefer it to be inside the car. I just couldn't find a good place for it inside the car since it has to communicate with the EFI ECM via a 4' long CAN bus harness.
In addition to numerous types of weather tight cases, Polycase also offers vents for the cases. The vents are also water tight (there is some type of membrane in the vent that allows air to pass but keeps moisture out). The Polycase waterproof offerings meet various IEC, NEMA and UL specifications - basically they are rated for outdoor use and can withstand some heat. Here's a link to Polycase: https://www.polycase.com/
DC
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,027
I'm putting the ECM for my Edelbrock Pro-Flo 4 EFI system and the Compushift controller for my 4L60E transmission in the right fender area between the back of the fender and the firewall. I'm being **** about it and plan to install both in weather tight enclosures from Polycase and then place a heat shield in front of the installation. Might be overkill but Compushift says that even though they allow the controller in the engine compartment, they prefer it to be inside the car. I just couldn't find a good place for it inside the car since it has to communicate with the EFI ECM via a 4' long CAN bus harness.
In addition to numerous types of weather tight cases, Polycase also offers vents for the cases. The vents are also water tight (there is some type of membrane in the vent that allows air to pass but keeps moisture out). The Polycase waterproof offerings meet various IEC, NEMA and UL specifications - basically they are rated for outdoor use and can withstand some heat. Here's a link to Polycase: https://www.polycase.com/
DC
In addition to numerous types of weather tight cases, Polycase also offers vents for the cases. The vents are also water tight (there is some type of membrane in the vent that allows air to pass but keeps moisture out). The Polycase waterproof offerings meet various IEC, NEMA and UL specifications - basically they are rated for outdoor use and can withstand some heat. Here's a link to Polycase: https://www.polycase.com/
DC
Le Mans Master
Joined: May 2003
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From: Fernandina Beach FL
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Melting Slicks
Joined: Apr 2001
Posts: 2,030
Likes: 363
From: Lubbock Texas
I looked into this option but didn't have the room. I have '79 seats in my '73 and there just wasn't enough room given the way the wiring harness connector plugs into the module. Can't raise the seat any because my head already hits the top.
DC
Thread Starter
Pro
Joined: Jan 2016
Posts: 502
Likes: 103
From: Reno Nevada
Under the seat is my preferred option as well, but according to Holley, there is no extension although perhaps it can be made. Not sure. There is plenty of loom from the ECM to the battery to go in either location, but the loom from the ECM to the engine is only 3-4 feet long. I can't be the only person with this issue...
Definitely would prefer it inside if I can make it happen. I will look into the seat idea. Will have C5 seats in mine. Not much room under there, but perhaps. Wiring is not my strong point but I will struggle through.
Thanks for the tips.
Definitely would prefer it inside if I can make it happen. I will look into the seat idea. Will have C5 seats in mine. Not much room under there, but perhaps. Wiring is not my strong point but I will struggle through.
Thanks for the tips.
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Thread Starter
Pro
Joined: Jan 2016
Posts: 502
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From: Reno Nevada