Re: What kind of amp kit should I buy for a 4 channel amp and future sub amp?
A 4 ga OFC kit is plenty for that level of power. You can add a distribution block and a bit of 8 ga wire to split the power when you add the second amp. I do this for my SQ setup with 700W and 2 amplifiers to the front speakers and 650W to the sub. Just make sure it's true 4 ga cable, not the cheap undersized CCA stuff. You'll also want to do the Big 3, or at least upgrade the grounds from the battery to the frame and from the battery to the engine.
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