I think I know how to do this, but I'd like to know if I'm forgetting something. What I basically want to do is use an Infinity Double Din Head unit with Crunch 1-CR-MXB4125 amp ( http://www.justamps.com/Amp_Pages/Crunch/crunch_blackmaxx.htm ) to power the 4 stock speakers, and Lexon tweeters in the dash. I got this cable ( MITAH http://peripheralelectronics.com/2002/loc.asp ) to go from the HU to the amp.

So...is this all I need to do?

1) run RCA cables from HU to the amp RCA inputs.
2) connect ANTENNA ON cable from HU to AMP TURN ON on the amp
3) Ground amp
4) Run +12V wire from the amp to the battery

yup. make sure the 12v+ is fused close to the battery. a good place to run the wire is under the glove box on the firewall, through the factory (large) grommet. another tip: hook up the ground, 12v+, and remote turn-on wire first, then power up the headunit and make sure the amp turns on. if it doesnt, you might have a bad ground or power supply issues. if it does turn on, your good-to-go and you can hook up the RCAs and contue on. the only reason i recomend this is ive seem too many people who dont adiquetly ground the amp and end up burning out thier headunits outputs.

just realized...you forgot to meantion hooking up the speakers to the amp. i assume that was impied though

:shhh: i do cocaine :/shhh:

hmm...arent the speakers already connected via the headunit cable? I dont have any subs. Basically I'm using the Crunch amp to make a hobo Infinity sound system.

no, you will have to tap into the output wiring of the factory amp in order to send the signal from the aftermarket amp on to the stock speakers. what that harness does is to output a signal via RCA cables, instead of the round connector. its just a way to get a signal from the factory headunit to an aftermarket amp. from the amp on its up to you to find the speaker wires and hook them up to the aftermarket amp. ive never worked on the stock infinity system, so im not to sure how to go about doing that...maby someone with a little more experience in this field can jump in?

:shhh: i do cocaine :/shhh:

I never had the factory amp...as far as I know the speaker wires are connected to the headunit harness that plugs into the back of the radio. If I have to run wires from the amp to the individual speakers, what do I do with the existing wires that are running into the factory harness?? Hacking up the harness doesnt seem right...

LOL..i figure this out soon hopefully

i assumed that the infinity system was set up like this: the headunit outputted the signal via the round connecter to an amp, then the amp was hooked up to all the speakers. i always thought the amp was located under the drivers seat, but i could be waaaay off here. from what i can tell by looking at the harness, it converts the output of the headunit to RCA audio plugs. thes would go to the amp and input the signal, but the problem seams to be where the speakers would be hooked up. they cant still come off of the headunit, as this would null the idea of having an amp. no matter what you are going to have to cut into a harness somwhere, im just not sure of the location or wire color codes of the speaker wires. if there is NO amp, and the speakers are run straight off the headunit, then you would need to cut into the wires behind the radio. if there is an external amp somwhere, youll need to cut into the harness at its location. i looked for a while online to try and find some kind of installation guide for the stock infinity system but had no luck. perhaps you should just call your local circuit city/best buy/audio shop and ask them what is involved, as they will probably have more experience interfacing aftermarket components into the premium stereos.

:shhh: i do cocaine :/shhh:

Ya know...I know what you said made sense, but I was thinking that the Infinity system was different because of what I read about it on various messageboards. When I looked under my passenger seat I didnt see any harness there, and assumed that was the way all the Mitsus were wired, so that wierd propietary cable was bidirectional or something, which was why no one ever wanted to do anything with the Infinity system stuff and aftermarket stuff. It would also seem like a pain if you wanted to replace the infinity head unit with just an aftermarket HU and bypass the amp, because you'd have to run new wires. You're right, there isnt any guides for doing anything with the system. After I read your previous post I thought about it and decided to just get some speaker wire and do it the way you would normally do an amp, just like the picture in the amp user guide and the amp installation kit! Seems like a lot of wire tho, RCAs going from the head unit all the way back to the hatch where the amp goes, then speaker wire all the way back to the head area to connect to the factory speaker wires! Even if I went with another aftermarket head unit it looks like I'd still have to do all that wiring. I guess thats the way everyone does it....

One more question...the MITAH wire adapter has what looks like a 24 gauge amp on cable with the RCAs. The Monster Cable amp install kit includes a 10 gauge amp power on wire. Now, do you guys think I can just connect the two? Or should I forget about that wire and connect it to amp wire in the stock harness? Or should I get some 18-24 gauge wire to match the factory wiring and run that to the amp?

im so sorry man, i wish i could help you out more! i need to get ahold of someones car w/ a fatory infinity system in it so i can know this stuff for future reference.

the small wire on the MITAH harness goes to the remote tur-on terminal on the amp. you only need a small guage wire here, 18ish or so guage. the main power wire, however, will need to be much larger; the size depends on how big of an amp youve got. i would assume you could just use the stock power wiring if you know where it is and everything, that way you wouldnt have to fool around with running all new wires. keep in mind that that 10 guage is only going to support an amp up to about 250 total RMS watts, so if you have a bigger amp get some bigger cable.

:shhh: i do cocaine :/shhh: