Is there any reason you shouldn't connect your amplifier directly to the battery negative instead of chassis ground on a cobalt? Do most use chassis ground because running a long wire back up to the engine compartment is inconvenient? On the SS (actually all the cobalts) the battery is in the trunk, so would there be a downside to doing this? My stuff isn't installed yet, and a friend recently asked me if there is a reason why people don't do it, or if there are any gains/losses from doing it. I didn't have an answer, and planned on just using the chassis to ground everything....but the battery is right there.... Thoughts, ideas?

 

If you follow the chassis of pretty much any car you will see it leads back to the negative post of the battery. The electrons are flowing through the chassis in almost the same way they would flow threw wire. The only reason why people don't run it all the way back to the battery is because of the extra work, space, weight, and money involved in putting an extra wire there.

 

To be honest it dosnt matter. I install computers and other electronic equiptment in cars, we almost always ground to the chassis.. and grab power from the battery. ALso a ground is just a ground, its not like (+). All chasis grounds lead to the battery ground...its a whole circle. so there ya go

 

I know the battery negative runs to chassis ground.....But would there be any benefit or drawback to cutting out the middleman?

 

as long as you grab a good ground you wont notice the difference. All I can think of is the less wire you have, the lesser chance of failure. If you want to run your ground to the battery you can to make the install nicer/cleaner being that access to aftermarket electronics wiring can be secluded in one spot. In other words..its up to you..

 

I ran my ground to the same spot where the battery grounds on the chassis. There's already a nice bolt to hook a ring terminal to there.

 

Our cars were made so easy to install electronics. I love it. Oh and yes wire it right to the battery.

 

I have been installed Audio Systems in cars for the past 6 years running. I never grounded an Amp to the battery. Your ground wire needs to be as short as possible to reduce the amount of noise in the system. The longer the wire the more chance of getting interference in your Audio System.

 

You know our battery is in the trunk. Where the amp will be right ? So the wire will be really short

 

Yes I know the battery is in the trunk. If your adding an amp I assume you will mount it to the back of the seat. If you do that you can ground it to the seatbelt bolts. which will be the shortest distance. Which means less noise. Also if you wire your amp to the battery and you have a short some where you battery will drain.
Some people don't relize that even when you amp is turned off it still draws current. Especially through the ground.
If you notice every ground wire in any car is grounded to the chassis.
Why change that and ground it to the battery. Just imagine how many wires their would be if everything was grounded to the battery.

 

look honestly alot of people have wondered this and its grey area but alot easier in a cobalt let me tell you some facts

The longer the ground the bigger chance of noise in the system or an electrical fire (fire being rare especially if you use the proper size wire but you need to make an informed decision so i threw it in there)
The shorter the ground the less chance of the above 2 things but also it will help your amp by lowering the overall resistance of the wire.
The resistance of the battery neg is the lowest resistance you will normally find in any car.
THe resistance of everything else varries... alot but usually whats considered the "frame" has the lowest resistance besides the battery.
All the above resistance other then a long ground is usually very close together (meaning your seatbelt bolt may have 0.01 ohm vs the battery of 0.0001 ohm)
Current will flow the path of least resistance period. meaning if you ground to the best point in the car and also the worst point in the car it would be the same as doing only the best

Now with that being said all hardcore spl guys ground to the battery neg at some point but they ususally opt on doing both... and since our battery is right there in my eyes it would be worth the what 4 ft to do both. Now if its a small system and wire is at a premium in your eyes then theres a good chance you wont notice a difference but if its a large one and you may have any problems with dimming of lights ect since the battery is right there it may solve alot... then again it might not but assuming whatever wire your using is 1 dollar a foot (probably cheaper) then im pretty sure 4 bucks or so is a good investment

 

It doesn't matter whether you wire it directly to the battery or the chassis, it's the same thing in the case of a short. The battery is connected to the chassis and the chassis acts like a big wire going back to the negative terminal of the battery, no matter where you connect to the chassis (as long as its good metal and the paint is removed). The amp may or may not draw a tiny amount of current when it's off, but if it does the amount is very small and where its grounded has nothing to do with that.

Every ground wire in any car is grounded to the chassis because that is usually the path of least resistance to ground.

Emperor is right on the money in his post. The only thing I would add is that if you hook the ground directly to the battery which has .001 ohm(or whatever small amount) less resistance than a seat bolt, the resistance in the longer wire required would offset any gains.

 

pretty much the only reason you hook it up to the chasis is so that you have less coming off of the battery, IMO it just looks cleaner