Firewall Penetration - for power lead, antenna, cable, etc from under the dash to the engine compartment?

[Ultraspaz]

So after balancing my options I decided on going through a grommet instead of drilling a new hole for adding wires through the firewall. I ended up using the grommet directly behind the battery.

Careful to avoid hitting other wires I punctured the grommet using an aluminum arrow shaft sharpened like a fountain pen. It went through the grommet fairly easily and I then ran a cord through the hollow arrow shaft for pulling wires through. I used dielectric grease to help slide the wires through but dish soap works well too.. So far I've managed to run a pair of 10 gauge wires for a ham radio, a 1/4 inch cable for a 6 gang switch and a couple of smaller gauge wire. I bundled the wires with a split wire sheath and sealed the hole in the grommet with automotive RTV sealant.

So far so good. No smoke, flames or error codes.

The 6 gang switch and relay setup I installed will let me add exterior lighting/accessories in the future without having to go through the firewall again. Everything can be routed to the fused relay box mounted in the engine compartment and switched by the controller on the dash.

 

[NavyBOFH]

So after balancing my options I decided on going through a grommet instead of drilling a new hole for adding wires through the firewall. I ended up using the grommet directly behind the battery.

Looks great! That is about identical to what I am planning on doing. My only concern now is 1) radio deck mounting, and 2) antenna location. How are you tackling those?

 

[Ultraspaz]

Looks great! That is about identical to what I am planning on doing. My only concern now is 1) radio deck mounting, and 2) antenna location. How are you tackling those?

My receiver will fit perfectly in the depression below the drivers seat. I have a VGC VR-N7500 dual band. I bought it because it's dimensions are perfect for under the seat. It also has no controls except an on/off switch. All frequency, squelch, memory changes etc. are bluetooth controlled via a spare cell phone. Other then so far it works when I tested it I don't know a lot about the radio. Probably Baofeng quality without the online support so I'll have my Yaesu HT for backup. I also have the Torque app on the spare phone to monitor engine parameters from an OBD2 bluetooth dongle. Pretty cool I can change frequencies and watch my engine temps on the same screen.

As for power. I ran a direct power and ground to the battery. To keep from forgetting to shut off the radio I installed an APRS Automatic Power Off (APO3). It detects voltage spikes when you start the car to bring power on then detects the voltage drop when you shut the engine off to kill the power after 10 minutes. Really slick set up.

I haven't installed the antenna yet but I'm using a Diamond K9000LRMO NMO motorized mount that lowers the antenna with a small dash mounted switch when I go in the garage. I'm mounting that on the rear luggage cross bar. As far the coax I think I may go through the liftgate then along the bottom molding to under the drivers seat. I can't get myself to punch a hole in my new roof yet. It took me 2 days to get the courage just to stick a hole it the grommet!

 

[JamesT]

I’m still interested in the idea of the bracket on the a pillar if that would work fir antenna

 

[JamesT]

i'm liking that concept. I found this install video for the F150 Raptor which i think is what you are describing. Once the Rigid mounts come out.

Today, I heard from Rigid about the A Pillar mounts. "We are working with Ford directly to design these mounts. Right now we are in the testing phases and should be moving forward with the launch in the next few months or so." So that's good news.

 

[HungLo]

So after balancing my options I decided on going through a grommet instead of drilling a new hole for adding wires through the firewall. I ended up using the grommet directly behind the battery.

Careful to avoid hitting other wires I punctured the grommet using an aluminum arrow shaft sharpened like a fountain pen. It went through the grommet fairly easily and I then ran a cord through the hollow arrow shaft for pulling wires through. I used dielectric grease to help slide the wires through but dish soap works well too.. So far I've managed to run a pair of 10 gauge wires for a ham radio, a 1/4 inch cable for a 6 gang switch and a couple of smaller gauge wire. I bundled the wires with a split wire sheath and sealed the hole in the grommet with automotive RTV sealant.

So far so good. No smoke, flames or error codes.

The 6 gang switch and relay setup I installed will let me add exterior lighting/accessories in the future without having to go through the firewall again. Everything can be routed to the fused relay box mounted in the engine compartment and switched by the controller on the dash.

Oh that switch box looks pretty cool. Can you show details on how you hooked it up to the fuse box?

 

[jnot2]

Well its been awhile and looking for any updates. BS BL should be here sometime in Feb. and will be installing an ICOM 5100 also. Looking for any information on the Rigid A pillar mount

 

[NVSport]

There’s a round grommet on drivers side door which has easy access, it pops right out.
I used a couple of long zip ties to fish my wires through. The hole under the dash is about 2” lower than the opening where the grommet is so it takes a bit of fiddling to push it through. I just cut a small hole in the grommet to push my wiring through. Zip tied the wiring up above pedals etc and you can push wire through behind the heater box easily to get it to the interior fuse box.Some pics attached:

 

[MDwayne]

There’s a round grommet on drivers side door which has easy access, it pops right out....

Interesting spot for engine access. Keeps the firewall integrity. I was wondering, though about whether the wiring gets crushed by the door which over time could be damaged and short or it's compromising the seal from the outside environment. I live in a place where if it's not raining and we see a really bright object in the sky (not sure what it's called), we all run to underground shelters - it's very scarry (^_^).

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