I've never installed my own car stereo before, so I was wondering what is the safest way to power a 400watt amp (for my speakers)? Do I hook it up to the battery?

My main question is also how to get it through the firewall. What is the best route?

Sorry if posting this question about a Grand Prix is a sin I didn't know what forum to go to.

Yes, you run a power cable to the battery. Make sure you have a fuse or breaker switch installed with that or you could start your car on fire. I don't know GP'* but on the Bonneville if you need you can run the power cable in between the hood and door. I'm sure someone that'* worked on GP'* will chime in, so my word isn't the final one.

I think that the way with goin under the hood and thru the door is kinda risky because it could get pinched. When i put on in my bonne i just pooked a hole thru the rubber thing thats under the dash where the steering thing went. Its rubber idk if you have one of your car but thats how i did mine.

trace back the path of your engine wiring harness where it goes throught the firewall. Unscrew it, get a mini-hack saw and make two cuts and bend back the sheet metal. I routed two 4-gauge wires along with some other wires through. The wires will end up underneath the passenger kick panel, you can then run it under the lower rail trim (pop up the trim, peel back carpet, run it along with the car wiring harness wires already there) , and into the trunk. This method assured that i would not pinch any wires or underneath the car where it could be damaged.



Ive done this to two cars with no problems, ask if you have any questions, i have more picks of my stereo install. This is how the pros do it.

thats a pretty good idea i never thought of doing it like that.

On H and W body cars you take out the passenger washer bottle and there is a small gap of firewall you can drill through. It comes out right below the heater box behind the glove compartment. I used it the last few times I did newer Monte Carlos. That way the wire runs on the same side as the battery and you dont have to waste 6 feet of wire going around the engine compartment. You should also look into getting a Side Post battery bolt that has a screw in the end of it to connect a ring terminal.

Heres a couple of tips for your install.

Run the power wire on the same side as the battery (if possible)
Fuse the wire within 18 inches of the battery.
Use a grommet through the firewall if you drilled your own hole.
Run the RCA cables as far away from the power cable as possible (typically along the other side of the car) , and away from anything that might have AC current (power inverters) and if they have to come close, minimize the area that they are side by side. Cross them at a 90 degree angle if you can.
Avoid bolting your amplifier onto a metal surface without insulation between the metal of the amp and the metal of the car. You can get ground loop interference.
Keep your ground wire from the amp to the chassis as short as possible and sand the area that the ground wire touches the body.
Careful you dont pull too hard on the RCAs or when you push them under panels. They can get damaged easily and can let noise in.

Never run wires through the boot around the steering column or any moving parts for that matter.
Thats an accident waiting to happen.

Your better off to drill a hole and use a rubber or snap in grommet.
Typically since firewalls are used on multiple vehicles with the same frame/body, a lot of times the foam padding is notched were a clutch or a factory harness would go, this is usually a safe place to drill, but always a good idea to double check before drilling.

Regards,
Dutch