Hey guys. I have had my evo for about 3 months and i finally needed to find the hole in the firewall for an installation. I cannot seem to find a factory one. I heard that we dont get one in evo from the factory. Do i need to drill one?

Thanks in advance

Matt

 

It's on the passenger side behind the glove box...almost in the top corner.

 

Go under the hood and look at the extreme left with a flashlight...it has a rubber plug in it.

 

i cant believe that there is a hole in the firewall after i drill one in myself for my system upgrade.

 

A good way of running wires is too run it through ther fender. There is an opening near the front of the fender that goes into the well cavity. run wires in there and puch hole in rubber grommet which comes out near the side of the glovebox. Its easy clean and you can run endless amounts of wires through there.

 

Moving to Evo H/T Questions.

 

What do you have to do to access that hole in the firewall from the inside?

 

I ran some wires and some vacuum hoses through both fenders pretty easily. I had an aftermarket cruise control installed and they mounted it in the only available space to drill holes through. Just take out wheel well liner and it is pretty easy to run the wires into the cabin. On the drivers side, you'll have to cut or drill a small whole in the existing rubber gromet for the cars wiring harness. This is an option if you cannot drill a whole or the extra passenger side grommet has already been used.

 

There are three options. There are the two fender routes as others have suggested. in fact, this is where the optional gauge wiring is installed. The other passthru is on the passenger side of the firewall tight against the outside behind the passenger wheel well. There's a rubber grommet there. There's also a place near the throttle cable that you can drill a hole through. I've done that too for my boost gauge install.

 

Screw that stupid rubber grommet. I worked my *** off trying to get some lines through that thing. The easy (and much quicker) route is to drill a hold in the firewall. See the two attached pictures. One is under the glove box and the other is inside the engine bay. Line yourself up with a bolt as shown by the arrow on both pics so you dont drill into your anti lock brake tuging. The 03 evo is shown and I have no idea what the 04's and 05's look like so do so at your own risk.

The firewall is two sheets of steel or aluminum with rubber sandwiched in between. So don't freak out when you break through the first sheet and find you still have more to go... Watch the insulation as it binds up in the drill when you start and when you break through into the engine bay and pretty much any time it touches the drill bit. Never tried the fender route as I never had anything going that way. Patch it up with some silicon if your hole is much bigger that what you pass through.

My 2 cents.

 

I pulled a 4 gauge wire for my amps through that grommet. It took about 10 minutes to find the grommet, cut a hole in the center and thread 12 feet of thick wire into the passenger compartment. The secret to doing this, like many things in life, is proper lubrication. Spraying a little silicone or wiping the wire down with some vegetable oil helps keep things from getting hung up. Any new wires I need to run will be run through the fender route. No more drilling holes into the firewall for me.