if i were you i would get an aftermarket headunit it makes it much easier plus it makes your speakers sound much better plus it allwos you to control your amp from the head unit its very nice plus it looks better than the stock unit
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magnaflow true dual exhaust, CAI, demon coil, livewires, xcal3 flashtuner, steeda short shifter, limo tint, 20" black boss wheels, foglight kit, mach 1 chin spoiler
If you want to just throw in some low end (subwoofers) You'll need the following
Box Subwoofers Amplifier LOC ( Line Output Converter ) Wiring kit (at least 4 AWG)
A new H/U changes things juuuuust a little bit but will make it easier for upgrading the rest of your system later. Like was previously stated, BEFORE YOU DO ANYTHING, let us know your goals and budget, and we'll get you going in the right direction.
Hey guys, just got back from Colorado... but yeah, back on topic:
I have 2 Memphis 12inch subwoofers... 800 watts a piece, together 1600 watts peak. I had a custom ported box made for my car that follows the air space specs of the subs.. i bought a competition amp kit with the 4 gauge power and ground wires... it came with the RCAs and all that good stuff to get it connected... i also bought a PAC line output converter, and now I just need my amp.. any recommendations?
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installing subs and & amp to stock system of a 2003 mus... - 
