ok i have a amp installed right now in the car and i want to add anotehr one i got the new ammp and the 4 guage kit. No local shop can install it for atleast 2 weeks and I dont want to wait. ive been able to install speakers and decks no problems and i got tools. I need help on how to isntall it i have the hole in the firewaall already because their is one hole for the existing amp poewr wire. I need to know what to do how to take off the side panneling or if to just take out seats and take out carpet..i dont mind lumps easily hideable. anyways anyone have any specifc detaling on how to do this for a 99 civic lx sedan. i just dont wanna wait 2 weeks for it to be installed when basically i hvea la the tools and thier is a hole already. ive tried googling it many times cant find anything. anyoen out their who can help me? thanks .
I would replace the current power wire you have with the 4 ga. Run it into a distrobution block and have 8 ga go from there to each amp. You can tuck the 4 ga under the carpet along your foot panel. Make sure your RCA cables are ran on the opposite side of the car to elliminate engine noise. Your 4 channel amp should have a pass through so you can run another rca there to your other amp. Here's a neat trick for connecting your speakers to the 4 ch amp without running alot of new wire. Run new wire from the amp to the rear speakers since they are easily accessed in the trunk. Here's the short cut.- Now run the front speaker wire from the 4 ch amp to the rear speaker wires that used to come from the HU., and behind the HU unit you want to connect your rear right wires to you front right wires and perform the same for the left side. This way you are using the existing wire in the vehicle to power your door speakers without actually going into the doors. Your car is a 99 so the wires should be fine. Good Luck.
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Do it right the first time
well the previous install was the install for the Infinity COmponpents kappa perfects 6.1. he already routed new wire to the back of the headunit so im fine their. i have 4 guage and do i need 1 distro block or two . my friend said to run the negatives to a distro block aswell less holes to drill.
That is common. Run 4 ga to distribution 8 ga out to amp for power and one common 4 ga ground to distribution 8ga out to amp.
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2004 Mazda 3s Hatchback
2- MTX 4500 8" subs powered by MTX 251D
ok but shoudl i run the power wire on left or right side of car i can easily run it on left side i see the hole that is left its coverd by plastic seal but easily remoeable my battery is on right side i have 21Ft of power wire. also i dont wanan drill a bigger hole on the right side of firewall beacuse the 10guage in their is running on right side but i dont think a 4 guage is gonna fit ill try tho. cant i run the two 8 guages to 2 diff grounds on the car ?
Hi, i had the same inconvenience with regards to the battery placement. I hav a 2 amp setup as listed below, but wat i found was: If the standard power wire isnt long enuf, there will be audio shops that will sell you the wire, so if nessisary go and buy the right length and run it the way you were first talkin bout.
Yes, with my setup i needed a fused distro block for the power wire, it ran 4 ga in and two 8 ga out. You will most likely have to remove your rear seats and most of the trims from both sides of the cars interior, it is a PAIN IN THE ASS, but once you have finally got it all installed it is worth it + you can say you hav done it too, so you get the greater satisfaction of havin installed it your self! 
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~* Cheer Nat *~
Pioneer DEH-7650MP
Pioneer TS-C160R
Pioneer TS-A6990S
Pioneer GM-6000F 4ch Amp
Audiobahn AW120T 12" Sub
Pioneer GM-D510M Mono Amp
AERPRO 1F Capacitor
thats the whole point i spednt 200 cdn for a amp and compoennt install took em 5 hours. i bet it would took me 8-10 LOL. but i wasnt happy cuz i didnt do it. i installed the deck myself i felt happy cuz i know how to do it. the thing is now the shipping co has LOST my amp and AMP kit so impissed off so i gotta wait a while. for the hell of it i might just run 4guage to my exisiting amp right now. wire is very expensive 4ugaue is 2 dollars a FOOT i need about 21 ft thats like 40 bux the amp kit that i bought with my amp was only 20US it had 21 ft of power wire and everythig n else im so pissed now. anyways i think it is best to run the power wire on left side of car even though battery is on right side. i find the plastic gourment on left side so their fole no hole drilling for me in firewall. ill just be long length of wire.