Is 8 gauge ground wire the same as 8 gauge speaker wire?Could l use 8 gauge speaker wire as the ''power wire'' for my car amplifier?

8 gauge wire is 8 gauge wire. what matters is what it is hooked to.

Before you come on here go google it.

they are the same

The differences between ur wires is the size of the insulation around the wire. If u look at power wire the rubber/plastic coating is much thinner than around speaker wire. The only reason for this is because the speaker wires need the extra thick coating to keep the wires from melting from all the power & since the wires carry alternating electric current they need to be separated more to keep them from creating the ''electromagnetic effect.''
As for using ur speaker wire as power wire, l would not recommend it but yes u can do it. 8 gauge wire is pretty small & l would consider buy a length of 6 or 4 to run to ur amp location then a distribution block to go from the 6 or 4 gauge wire down to 8 gauge & into the amp. Keeping ur wiring bigger is always a good idea to protect ur gear & it allows for u to expand ur system if u ever desire to.

hope this helps.

YES & NO. Yes they r the same #8 gauge but No they r not the same application. The speaker wires r intended to carry high audio signal or RMS voltage meaning the current flowing trough the speaker wires r in RMS wave which is in layman is term alternating - changes its direction every certain period. What am l saying & why am l saying this? Well the speaker wire can not be used for ur Power source or to power up ur amplifier simply because speaker wires have soft insulation & Power lines has DC direct current voltage that tends to produce more heat & thus can compromise ur car. The speaker wire is insulation can melt & u can start a fire & goodbye to ur car! Speaker wires r for speakers & Power wires r for Power source regardless of gauge. The gauge of the wire determines the current carrying capacity of the wires the larger the diameter (which is the smaller gauge#) the larger current it can carry. Can u use the speaker wire to power up ur AMP ? why not but it is highly unsafe & it is not professional & it is not right. Put it this way : It is better to use ur power wires for ur speaker rather than use ur speaker wires to power ur AMP.

jsc_ny is full of crap.

Wire is wire.