I've got a few questions here. I'm in the process of upgrading the Big 3 just to get it out of the way before I upgrade my audio system now that I have most of the necessary maintenance items done to my car. I've run 1/0 grounds and I'm in the process of upgrading the alt charging wire to the battery. That's been pretty straightforward.

I need to run 4 gauge to my amp in the trunk and I want to run it through the driver's side grommet to get it down the driver's side sill to the trunk.
For any of you that ran power wiring this way, how did you secure the power wire in the engine bay that runs from the battery over to the driver side grommet? The easiest way looks like up against the bulkhead behind the engine just below the plastic weatherstripping, but there's not a lot there to zip tie the wire to secure it. I'm worried about it sagging with heat. Did you drill into that bulkhead and put in zip tie mounts?

Also, does anyone have amp rack dimensions for the spare tire area? I had a pas2knut rack in my old car that I liked, but it looks like he's no longer active and if I can avoid fiddling around with cardboard templates, that would be ideal.

 

I ran my power cable like you are looking to do. I zip tied mine to the large cable by the firewall near the battery and then stuck a hanger with double sided tape against the firewall to hold it up. I also covered the power wire with a plastic sheath from the battery to the firewall grommet. Its been there going on 11 years now without problems. Regarding the amp rack, I used to 1/2" MDF covered with a grey felt like material that matches the trunk. Mine measures 13 1/2" wide and 10" tall. That is about the same size as my amplifier.

Good luck with your install.

 

Use military spec teflon wire (aircraft wire).
You can literally wrap it around engine and almost literally - around your exhaust and it'll be fine.

Not to mention it s extreme durable against sharp edges.