i can actually drill a hole into the firewall of my car to get an amplifier power cord through?

Question

if so, can i get a detailed despription of how to do it.

Answer 1

Usually, it's easier to drill from the cabin side of the firewall than the engine side.

Locate something that can be found on both sides of the firewall; ie, the hood release cable, main wiring plug, or clutch plate. This item is your reference point. Find an area of flat firewall metal near the reference point; make sure it's clear of obstructions on both sides of the firewall. The reference point item is there to make sure you're looking at the same part of the firewall on each side; ie, two inches to the left of the hood release cable grommet. You need to be absolutely sure it's clear before you drill.

Use a screwdriver with a self-tapping sheet metal screw to make a small hole in the firewall metal. Using a screw instead of a drill bit minimizes the chance of damaging something on the other side if you picked the wrong spot. Place a light source inside the vehicle, then look at the firewall inside the engine compartment for the light shining through the small hole.

If the hole is in the right place and it's clear of obstructions, use a step-bit or "Unibit" to drill the hole larger until it's big enough for the power wire and grommet. You need to use a rubber grommet or plastic bushing in the hole, or the wire will rub against the sharp metal edge and eventually short itself. Make sure there's a fuse on the power wire near the battery, and make sure you seal the hole with strip-caulk or silicone so that water can't run along the power wire through the hole and into the passenger compartment.

You're probably going to get people telling you to use an existing vehicle wire grommet to run your wire, instead of drilling a new hole. That's fine, but not every vehicle will allow you to do this. Sometimes you just have to drill.

Answer 2

Sure you can. If you watched a professional installer install an amp or anything, they have to do that if there is no existing hole to use. Be sure to seal up the hole so that no moisture can enter by using a grommet if you can. Ive installed a couple of systems in various cars Ive owned and have never had a problem.