After installing a new amp, I've come to find out that the stock power wire and ground aren't sufficiently large for the kind of power the amp puts out. So I need to replace them with one wire that goes directly from the amp to the battery and another that goes to chassis ground. I'll put a 15A inline fuse on the wire near the battery for protection, since I'll be bypassing the interior and engine compartment fuse boxes through which the stock wires pass.

What's the best, least disruptive way to route wires like this? It's not 100% clear to me where the stock wiring comes through, though I guess it must be coming out around where the coils are and then through the engine harnesses to the battery. I'm not in the mood to take off the intake manifold to route one wire, though. I don't have a heater core (I live in a desert environment). Could I route the wiring through the heater core pipes that go through the firewall? Could/should I just drill a hole in the firewall along the passenger's side and run it to the battery that way?

Any suggestions/advice much appreciated.

 

I'll get some Pictures of my routing for you in a little bit.

 

Excellent – would love to see that.

 

Completely forgot to get pictures. I'm setting a reminder on my phone to get them when I'm home this evening.

 

No worries. I'm not planning on doing this for a few days at least, in any case.

 

I drilled a hole next to the main harness pass through on the passenger firewall, then used a grommet to protect the wires. You just have to eyeball the distance and location, looking up from the passenger footwell.

The other openings are sealed. But if water gets that high on mine I'm screwed anyway.

 

Here's the picture! As you can see, I routed it between the fuse box and the coolant overflow then back to the firewall grommet. I cut a little slit in it with a box cutter and ran the cables right through.

 

This is brilliant, thanks for the pic. Seems like the place to go.