Bigger Battery and Alternator

[laceygirl]

Hey everyone,

Thinking of putting a much better stereo system in the car, and adding a subwoofer under the passenger seat, but the current battery and alternator wouldn't be able to handle it I don't reckon, so what would be an upgrade?

I'd like 4 speakers 2 tweeters and a sub, nothing huge.... It doesn't have to be, the car is little... Probably bigger speakers in the back, and ideally I'd like to relocate them to higher up somewhere (need to put some thought into that), but no more than about 500-600w for entire system including the Sat Nav and DVD.... Does that sound feasible or am I way off?

I don't plan on updating my lights to LED's so I'm willing to update the abovementioned..... When the warranty is up, I can play with the motor....

Any advice is appreciated...

Laceygirl...

[inuvik]

The alternator on the Mirage is rated for a maximum output of 85 amps. That's approximately 1200 watts of output. You're probably limited to about about 400 watts maximum draw for the stereo. You have to have enough power left to run the ecu, abs, fuel pump, headlights, air, power steering. It's a small car so there probably the better plan is to find speakers that are more efficient with better response. a reasonable amp, a good crossover and a quality sub-woofer

[ahintofpepperjack]

As far as I am aware, there is no upgraded alternator available. The mirage actually has a decent size battery, you shouldn't need to upgrade that. Also, You don't need Watts for a good sounding system. 600 Watts at 12.5V is 48 Amps. The mirage would not be able to support that. A 300 Watt setup would sound great and only use 24 Amps.

A small 50Watt RMS amp like this would be more than sufficient for the speakers.

Then a powered 8" sub to fill in the lows. like this.

[Cobrajet]

Get a lightning cap.

As others have said, the Mirage's charging system is quite robust for what it needs to do, so this should prevent any problems.

[alex16]

As far as I am aware, there is no upgraded alternator available. The mirage actually has a decent size battery, you shouldn't need to upgrade that. Also, You don't need Watts for a good sounding system. 600 Watts at 12.5V is 48 Amps. The mirage would not be able to support that. A 300 Watt setup would sound great and only use 24 Amps.

A small 50Watt RMS amp like this would be more than sufficient for the speakers.

Then a powered 8" sub to fill in the lows. like this.

Actually the Mirage battery is very weak.The OEM 55D23L is rated at 356 CCA, for reference a 20HP lawn mower premium battery has 330 CCA. The 350CCA is plenty for the 1.2L but for extreme power use such as dc to ac converters or amplifiers it won't last long.

I researched the 55D23L and subaru foresters used the same battery size, which converted to group size is 35.

I am not sure what battery brands you have over there but for us the Walmart Group 35 everstart maxx provides 3 year free replacement plus 640CCA. A capacitor and a higher output battery will help handle the added music much better, less strain on the electrical system and better sound. But beware, if you want to maintain a factory warranty they can deny your repairs if you have after market stereo wiring installed, as they have done for me with my warranty issues.

[laceygirl]

Thank you everyone... I need to go check under my bonnet and see what battery Australia uses... :-)

[ahintofpepperjack]

Actually the Mirage battery is very weak.The OEM 55D23L is rated at 356 CCA, for reference a 20HP lawn mower premium battery has 330 CCA. The 350CCA is plenty for the 1.2L but for extreme power use such as dc to ac converters or amplifiers it won't last long.

I researched the 55D23L and subaru foresters used the same battery size, which converted to group size is 35.

Cold Cranking Amps doesn't really matter in this situation. That is a measure of the Cranking Amps the battery can deliver for 30 seconds at 0 degrees Fahrenheit. 1. I doubt its going to be that cold in Australia. 2. You won't be cranking a mirage over for 30 seconds. 3. Our engine is tiny and doesn't need as many amps to turn over as larger cars do. There are motorcycles with bigger engines than our car!

Reserve Capacity is what matters. This is the actually amount of time the battery can supply power before it's voltage drops off. I don't know what our batteries supply in reserve capacity, but it is a fairly large battery for our small cars and I would think it's more than adequate. Especially if they are using this same battery in Subarus with 2.0L+ 4 cylinder engines.

[alex16]

My experience has shown these batteries in the mirage don't have the power you need, it will work but you don't realize the voltage drops at times, I used to be into car audio basics and the battery is always the first thing you replace, having a good main battery and a capacitor is a good start for a system. The real way to find out is to install the stereo and crank it with ac, lights, ect. On and check the voltage at the battery. In my Cherokee I run a 200w max head unit and a 400w sub amp and it can easily dim the lights when the engine is idling because alternator output is only 30-40a on idle, at 1500 rpm it can do 80a and the lights don't dim much but voltage can drop from 14.5 to 13.4 on hard bass (at 1500 rpm) and this is with a Walmart maxx, it still needs a capacitor to be efficient at idle.

[91cavgt]

I've got a JL Audio 250 watt sub amp under my seat connected to my under seat sub. The ONLY time the voltage drops is when sitting at idle with my lights on AND the stereo cranked. My alternator and battery are all stock.


Keep a couple of things in mind. Just because someone installs say a 1,000 watt stereo in their car, that does NOT mean that stereo is always putting out 1,000 watts. Amplifiers are not rated on the power that they put out when you are just normally listening to them. The RMS rating is full power, typically at 12.8 volts, and at less than a standard distortion rating. Rarely do you use an amplifier to it's maximum.

As far as an alternator upgrade, there is one available! But it only puts out 10 more amps than the stock one. The stock Mirage alternator from a car that has the auto start/stop system is a 95 amp alternator.


However, before upgrading the alternator, I would highly recommend you upgrade the power and ground wires on the car first. The power wire for the alternator is, maybe, an 8 gauge wire. Upgrading it to a 4 gauge wire would help to decrease the resistance and send more power, quicker, to the battery. But, just upgrading that power wire won't help unless you also upgrade the ground wires. The chassis ground wire coming off of the battery, and I would add a ground wire to the alternator that grounds the frame to the chassis as well with an equal size wire to the upgraded wire that goes from the alternator to the battery on the positive side.


As far as voiding your warranty, the only warranty they can legally void on your car if you upgrade the stereo is the radio warranty. Due to the Magnusson-Moss act, it is illegal and dealerships can get into trouble if, for example, they void your engine warranty because you have an upgraded stereo in the car.

[cyclopathic]

As far as I am aware, there is no upgraded alternator available. The mirage actually has a decent size battery, you shouldn't need to upgrade that. Also, You don't need Watts for a good sounding system. 600 Watts at 12.5V is 48 Amps. The mirage would not be able to support that. A 300 Watt setup would sound great and only use 24 Amps.

A small 50Watt RMS amp like this would be more than sufficient for the speakers.

Then a powered 8" sub to fill in the lows. like this.

as subs go I would probably go with this one.. much easier to fit under the seat.
http://www.amazon.com/Pioneer-TS-WH5...ords=TS-WH500A