it's more than safe to run amp wire under your car.....when i run it though, i usually push it through a 1/2" PVC pipe and ziptie it to the frame or wherever seems it would hold well.....

what kind of set-up are we talking? not many people that i know need 0 gauge wire for their system and i have 4 running through my car right now under the carpet on the INSIDE...so consider that....and i still say let a professional do it especially since you are arguing whether or not it's safe to run wire under a car....

do yourself a favor, look under any car that has underbody neons........it's self explanatory

 

ok, im running the 0ga under the car, because NJthunder5sd and i couldnt fingure a way to run it through the inside. sure u could get it through the firewall, but then were are you going with it? it wont fit along the sides of the car as its to thick. if you go though the center of the car, you'll have a big lump under the carpet where the wire goes. honestly i dont think anything that the car would kickup would damage the wire, even if it does damage it, its going to have to be something that will be big enought to damage a lot of other things under the car too.

oh, im running 0ga to a distro block which has 2 4ga outs to a 1500w amp for my sub and a 400w amp for speakers.

 

a zero gauge will fit throught the passenger side of the car behind the glove box then throught the plastic on the ground near the door then behind the plastic where the pasenger side rear speaker is and under the seat in to the spare tire storage compartment i tested it with a 4 foot scrap of zero gauge i have and it fit im going to actualy run on once i get my tax return and buy my second kicker 1200.1 and my second hifonics atlas

 

mmm.. Hifonics... I'm running a Hifonics Brutus BX1000D 1000w Mono amp right now.. I love it.