This crazy setup was actually created to cause stress and suicide about 15 years down the line when attempting to swap for new components.
Everything in the car is 8 Ohms. Everything. Anything I want to put in the car, or is worth putting in the car, runs off of 2 or 4 Ohms. Between the complex wiring (insanely so), and the Ohms requiRED / put out by the system, changing anything would either make the whole system not work, or blow out a new Amp or head unit.
Should I bother looking for a new 8 Ohm CD player and Amp, or should I just strip the whole car and start fresh with interchangeable parts?
First off what are you trying to do? install new speakers or a new deak leaving the factory speakers?
If you are trying to do the latter of the two and you are worried about the 8 ohm load on your deck, don't. 8 ohms to a 4 ohm rated amp will not harm it. In fact the amp will see less of a load, and therefore be "easier" on the amp. The only thing you lose is some volume from the speakers. This example would be if you have 4, 8 ohm speakers and you hook them up to an after market deck or just about any other after market amp.
However your suggestion of re-wiring the car would probably be the easiest thing to do in the long run, especially if you continue to upgrade.
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He's right. The higher ohm load does not matter. If you add a new deck it'd be best to upgrade speakers anyway to better your sound. You can either run new wires to all the speakers, or run them to the factory amp, and tie in there.
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My ex once told me I have a perfect face for radio.