ECU mounting location

[tmunroe22]

I have a 1971 Nova that I have put an ls3 crate in. I got the wiring harness, ECU kit from GM. im wondering where people usually mount the ECU and the fuse box? I'm a rac car guy and I would love to put it in the cabin, but that would involve a pretty good size hole in the firewall. Thanks in advance, I appreciate it.

[Just 1 More]

Mounted mine under the passenger seat and Yes, requires a 2" hole in the firewall
https://static1.pt-content.com/images/pt/2021/11/51291342170_e1720f1783_b-1.jpg (https://flic.kr/p/2m9rx4G)20210704_134327 (https://flic.kr/p/2m9rx4G) by F G (https://www.flickr.com/photos/153250783@N04/), on Flickr

[srode]

Mounted mine under the passenger seat and Yes, requires a 2" hole in the firewall
https://static1.pt-content.com/images/pt/2021/11/51291342170_e1720f1783_b-1.jpg (https://flic.kr/p/2m9rx4G)20210704_134327 (https://flic.kr/p/2m9rx4G) by F G (https://www.flickr.com/photos/153250783@N04/), on FlickrLooks like you are using a Holley controller? I don't think the wiring harness from GM is long enough to do that, it would have to be an aftermarket harness to get that far I'm pretty sure.

[79 Camaro]

I typically mount ECM, relays and fuse block behind the glove box. Mount the check engine light low enough so you can see it from drivers seat or extend the wires and put a light in the dash bezel. It gets kind of crowded but it has worked for me.
My go to place for various grommets is the local salvage yard. They almost give them away.

[sjaroslo]

It may not be applicable in your case but for my 67 Camaro, since I relocated the battery to the trunk, I put the fuse center near that space, on a simple piece of bent up sheet metal. For the ECU I purchased a 67 Camaro Rally Sport headlight door relay panel, which normally tucks up under the driver's side front fender, and mounted it up under the passenger side fender (arrows in the picture point out the mounting screws as well as a little bit of one of the connectors hanging down).

194298

[tmunroe22]

Thanks for all the help here. I will go behind the glove box.