Anyone running 4awg power wire through the factory firewall gromet

Was wondering if any of you with a system ran 4gauge wire without any issues or is it better to go with 8 gauge my amp is only a 4 channel 300 watt

 

Use either one or both of the vacant bungs on the passenger side firewall to run those wires - that way you stay out of the main loom and possible save yourself from a nicked/damaged wire headache.

 

thanks I didn’t know there was vacant ones

 

Not sure if it’s on the 2021, but the other 3rd gen’s had a plastic grommet right here



It comes out here (you can barely see the heat of a screw poking through the carpet)



slice an X in the carpet with a razor blade and push your wire through. 4awg fits like a glove (be sure to use a grommet to prevent the metal from digging into your wire)

 

Check the "Main Harness" grommet on the drivers side for an extra nipple below the wires.
The 2nd gens and Tundras have this, I cut the tip off of it and with a little baby soap/lotion easily feed 4ga from the cab to the engine bay.
On the 2nd gens passengers side theres also a "plug/blank' grommet that power can be ran thru, this one is a bit more work and requires a lot of F words to feed wire thru(engine bay to cab). You'll also need a new grommet for this.

 

I poked a hole down on driver side where factory harness go through. Clean straight run to the battery then. You can add a grommet if you want but not needed. 4awg no problem.

this was like one of the easiest parts of install

 

I have 2 gauge power and ground run through the factory grommet. Sounds like the 3rd gens got an extra hole so that's pretty cool. I'd utilize that if I were you. For 2nd gens (like mine) I always found the best way to do it was to carefully stab a pair of scissors through it and then open them to make the hole large enough to pass the desired wire through. Never failed me and I've installed a lot of systems. As others have mentioned, if you use the factory main grommet, just be careful you don't catch another wire...you'll spend a lot of money on that one. I can't even imagine.

 

Do you really need 4 awg?

At most, it'll be 25 A at 12 V.

Seems like alot of wire for the load.

 

maybe can use 8 awhile it’s only a 400w amp

 

8awg is fine for 400watt your fuse would probably shit out before 8awg got hot enough to be a problem unless you have like 100ft cable

 

did the math my amp is rated at 345 watts 4 channel(older alpine amp from 05) at 12.6 volts I’m at like 27 amps of power putting the amp behind the driver backseat rear cubby it’s about maybe 12 feet with the turns I’m guessing(running the power wire battery straight through the driver side all the way to the back) I’m guessing 8 gauge would be better but thinking I can get away with 10 gauge since the Rockford Fosgate wire kit I want to get goes from 15 bucks for the 10 gauge to 50 bucks for the 8 gauge trying to save a little coin if I can on the wire, I have some house 8awg pure copper wire laying around but not sure if I should use house stuff

Amp specs

• 75 watts RMS x 4 at 4 ohms (150 watts RMS x 4 at 2 ohms)
• 300 watts RMS x 1 (channels 3/4 only) in bridged mode
• Amp Link allows single cable connection for signal and control with compatible Alpine receivers
• 2-, 3-, or 4-channel output
• CEA-2006 compliant
• Tri-way capable (Tri-Way crossover required)
• variable low- and high-pass digital filters, 30-400 Hz or 600-8000 Hz at 12 dB/octave

 

My jl audio 300/4 amp calls for 4 gauge if it’s more then 6’ but if it was shorter then 8 gauge would suffice

 

Yeah think I did the math wrong at 150 watt rms x 4 at 2 ohm the amp is actually running more like 600 watts not 345 at class b roughly 65 percent efficient it’s more like 66 amps and there are two 30 amp fuses so it’s 60 which is close to what I got which would make it draw 60 amps at 10 ft I think I would need 4 gauge

 

more like 600watts/.65 efficiency = 923 actual watts used with line loss to get a 600 watt reading

923watts /12.6 volts = 73 amps

....now if you consult crutchfield a typical test tone only uses 1/3 of power of full scale rating so 73amps × .33 =

24amps

which aligns with general assumption that total amps is roughly half of total fuse ratings, in your case thats 60. So roughly 25-30 amp ballpark actual draw max. You are fine with 8awg. would make zero sense to have 60amps of fuse for 66amps from your calc. you need to i include that test signal factor as well. did you ever hear the stock 15watt or whatever rating above 50%? loud af.

When in doubt stick with manufacturer reccomended.

 

I would try putting it under the drivers seat, then 8ga would be perfect. Its about a 9-10foot run(I always make sure I have extra wire).

In the 2nd gens you just have to keep clear of a plug that hangs down from the seat.

I fit a pretty big bitch under mine. It's mounted to a 1/2" board of expanded PVC thats under the carpet.