Help locating [higher output] alternator (searched!)

[turbo98eclipse]

currently, my system is running at half power and im scared if i get another amp to run it at full power...my alternator will die!! (2 kicker l7's 1500 rms together or 3000w total) ive seen other posts and the highest ive seen was links to 135a alternators (for turbo models)...would the 135a alternator be able to keep my battery charged? i read on the page that "You can add your stereo ampifier up to 1500 watts and this alternator will maintain your battery." is that 1500w rms or total? and if this isnt good enough...could someone point me in the direction of a stronger alternator or just a different solution? thanx guys!

 

[DGajre777]

The question about weather your alternator will support 2 amplifiers does not depend on how many watts RMS you run. It depends on how many amperes your amplifiers will take.

Straight from Crutchfield...
Your car's alternator ampere rating determines how powerful an amplifier you can install. Multiply the ampere rating by 40%, and you'll get a rough idea of how much reserve current capacity your car's system has. Next, you'll need to calculate the approximate current draw of the amplifier you're considering installing.

To calculate the current draw of an amplifier, multiply the number of channels by the RMS watts per channel (a 2 channel amp rated at 300 watts RMS per channel would be 600 watts). Double it to account for amplifier inefficiency (600 watts X 2 = 1200 watts), then divide by the average output Voltage of an alternator, 13.8 volts (1200 divided by 13.8 = 87 amps). Since the average music signal requires about 1/3rd of the average power in a test tone, divide by 3 (87 amps divided by 3 = 29 amps). The result is the amplifier's approximate average current draw.

A quick way to ballpark an amplifier's current draw is to divide the total fuse value of the amp by two. For amplifiers with multiple fuses, the rating of all fuses provided with the amp must be added together. This will likely produce a significantly higher estimate than using the proper formula. Although inaccurate, this will err on the side of safety.

Finally, compare the amplifier's approximate current draw to your vehicle's reserve current capacity to determine if the electrical system can support the amplifier.

If you want more power than your alternator can service, you will have to consider having your alternator rebuilt for higher output — or invest in a high-output aftermarket alternator. (Sorry, we can't help you with this.) Installing a second battery won't help — that only allows you to play your stereo for long periods with the engine off. But, remember that any system playing at one-third volume is drawing considerably less current than the same system at three-quarter volume, and may not need a charging system upgrade if the volume levels are kept reasonable.

If your system needs more current than the alternator can supply, it starts to grab current from the battery — not a good thing for your car or your music! Here are a couple of warning signs to look for:
1) your headlights dim in time to the music when you crank it up loud at night;
2) your bass sounds great when you first turn it on, but gets mushy and less powerful within a minute or so.

One easy, effective solution is installing a capacitor. Heavy-duty capacitors connect to the power cable (just before it reaches your amplifier) and act as a buffer zone between your amp and your car's electrical system. They store up a reservoir of power which can supply the amplifier's peak demands (like a kick drum beat) without having to pull current from the battery.

The 135 amp alternator does not put out 135 amps until 3000-4000 RPM. Which means it might charge your battery on the highway but it will charge less than the stock alternator at idle RPM. The amplifier that you have is not a high power one and I think it has a 25 amp fuse (if I remember correctly last time I looked at it). You can have 2 of those amps and your stock alternator will support it.

 

[Old Mitsu Tech]

My only thought is to check an alternator shop to see if a higher output stator winding is available. Sometimes they can find what you need. Although 135 amps is pretty healthy. Second battery and 1 farad capacitors also come to mind.

Good Luck

 

[DGajre777]

My only thought is to check an alternator shop to see if a higher output stator winding is available. Sometimes they can find what you need. Although 135 amps is pretty healthy. Second battery and 1 farad capacitors also come to mind.

Good Luck

A second battery will only give more audio time with the engine off but it will take the alternator longer to charge two batteries. The only way around lack of power for high amp amplifiers is to get a higher output alternator or to find amplifiers that produce more power and take less current.

 

[Attack Eagle]

YEs or if it is a demo car only, add a dedicated alternator just for the audio system. Not feasable on the street.

 

[Old Mitsu Tech]

The best way is to build your components within the confines of the current charging system. I don't think they had stereo systems like these in mind when the charging systems were designed.

Good Luck

 

[napkinthief]

get a distributor and 3 farad cap, the cap will hold ## 3000 rms go the ebay route and itll cost you less than a hundred, otherwise you will spend into the 400-500 range

 

[DGajre777]

get a distributor and 3 farad cap, the cap will hold ## 3000 rms go the ebay route and itll cost you less than a hundred, otherwise you will spend into the 400-500 range

But that 3 farad capacitor will take more current to charge from an already insufficient charging system.

 

[Attack Eagle]

exactly... caps are what I think of as "battery relocation" devices... They compensate for the battery distance and the milliseconds it takes the battery's chemical process to create the demanded power.

You still have to MAKE the power somewhere, and either you make it by draining the battery, or from the alternator.
Stay away from current hog amps. No reason in a hatch back that you NEED that kind of wattage to get even "internal organ rearranging" bass. And if you plan on a lifetime of enjoyment, instead of early tone deafness, you don't want to.