I am running two 4 gauge wires to the trunk...I've plotted the path and the best way (as other have mentioned) is thru the firewall on the passengers side under the glove compartment.

the big question is where is the best spot?

there is a bolt/nut under the glove compartment against the firewall....is that the same bolt/nut that connects under the window washer fluid tank?

if so, then based on that point how far to the right and up/down should I drill?

also how thick is the firewall?

THANK YOU!!!

(the DIY on this is missing all the pics....so I am running blind on this)

bump

why are you drilling through the firewall when you can run the wires through the rubber grommet on driver side? i know i've seen the diy for the glove compartment drilling behind the washer fluid tank, but i never understood why.

two 4 gauge wires is why....both over 1/2 size

I've seen the rubber ont he drivers side...way to small...plus many more electronics are run that way....and battery is on drivers side...shortest ground is the best ground

Don't drill!

If you take out the washer bottle, there are two grometts, one is huge - it's where the JDM steering column goes! Even the small one is big enough for your wires.

S

thanks stealth!

this deserves a double thank you!

Picture of my 4gauge wire. Hole above that is for my greddy harness plus other senors for my guages.

a triple thankyou as im planing on running my amp this week

washer fluid tank is gone...ok there are no rubber gromets on mine :(

so I'm drilling it seems

btw ground return through chassis ground is miserable...run a direct ground return to the battery...a seperate one

Picture of my 4gauge wire. Hole above that is for my greddy harness plus other senors for my guages.

what is behind here?????

what is behind here?????


You've got a good 2 inches of free space behind the hole to work with. You'll see some sound insulation stuff when you drill through.
Get a clothes hanger and run it down the hole, feel inside on the passenger side, cut a slit in the rubber wall. Tape the wire to the other end of the hanger, run it through. I routed mine underneath the center console to the trunk.

thank you adrian....I'm going to drill right now :D

holes drilled :D that was a piece of cake...well kind of :p

the largest drill bit I could find was 1/2...that is fine for cramming the wire in there but I have some nice hard plastic firewall passthrough grommets that are slighly bigger with a diamter designed just for 4 gauge wire...so I had to dremel the hole bigger

unfortunately one of the holes I began to drill was causing trouble so I have 3 holes :o 2 almost perfect ones and 1 funny one...I'll jam a rubber stopper in there for now...but it should be ok since it is about 5/6 gauge in size and behind the washer fluid tank

thanks everyone for you help!!!!!!!!!!!!

....on US cars, these grommets house the heater and a/c lines, and they ALL fit thru one hole!

It should be hard to miss?

S

I see the gromit you speak of but it is not suitable for running 4 gauge...right now I've got the wiring through the holes I drilled...the fuse holder is mounted...I'm now attaching the postive...and soon the negative...I actually decided to cut a hole in the battery cover :)

then I'll run it along the side of the car under the interior scuff plates...under the rear passenger seat and into the trunk :D

my back hurts :(