Which wire would you recommend?

Hi,

I recently installed a small 85x4WRMS Amp under my drivers seat in my car to power my four 250WRMS door speakers. At the moment I am running the Amps output back up to behind the car stereo to the factory speaker wiring. I would like to run my own wiring to the doors though. I've also got a 600WRMS Amp in the boot that will eventually run a pair of 12" subs when I get around to buying them. I'm currently using 8 Gauge wire to power the under-seat Amp. 

So heres my questions:

What size wire should I run to the 250WRMS 3-Way speakers?

1.  16 ga. speaker wire.

2.  DO NOT double up power wires to the same amplifier.  Buy a new wire and fuse if you need it.  (..and two 8 ga. does not equal one 4 ga.)

3.  No.  Ground directly into the sheet metal floor pan.  Remove and clean all traces of paint and bolt / screw securely.

You can certainly power the sub amp with a separate power wire.  It would be attached to the battery positive as well as your other amp's power wire, but it must have its own fuse.  In a way, I guess you could say they would be parallel, as such.  But they wouldn't be referred to that way.

Thanks for the reply.

I will purchase a roll of 16ga next week and wire the door speakers directly from the underseat amp. The price difference between 8 gauge ($3.62/m) and 4 gauge ($18.50/m) is rather large so I'd rather use two 8 gauge running side by side and joining at the fuse holder, and the other side on the amp.

So would running two 8 gauge wires give me any more current handling than just running a single 8 gauge wire. Is it worth spending the large amounts of money on 4 gauge?

Thanks.

Hey, its a 600W RMS Amp putting out 1800W Max. It has 3 25A fuses on the Amp so I assume it needs around 75A capable power wire? Last I checked 8 gauge was only up to around 55A - 60A. I have blown a 40A fuse with this Amp and it wasn't over half volume.

So yeah, would wiring 2x 8 gauge wires allow it to be able to carry more amps. Cheers.