2003 Expedition 6G alternator upgrade.

[2003FordGuy]

Has anyone ever upgraded thier 2nd gen Expy Alt to a high amp 2015 Ford Superduty 225 amp alternator? Has the same exact 3 prong plug and same mounting. Just not sure if I'll overload the electrical system or burn the ecm. Thanks.

 

[stamp11127]

That isn't how it works. The higher output will charge the battery quicker than a lower output alternator. In order for it to ramp up to max output the battery would need one hell of a load on it and drop the voltage a large amount.

 

[2003FordGuy]

That isn't how it works. The higher output will charge the battery quicker than a lower output alternator. In order for it to ramp up to max output the battery would need one hell of a load on it and drop the voltage a large amount.

So what would you suggest stamp11127? My issue is my 2300 watt 1ohm monoblock amp. The amp drops the voltage down to 11 volts according to my 60 sample per second digital voltmeter. I'm running 2 yellow top Optima, 0 gauge lead power cable, and a 135 amp alt.

 

[stamp11127]

That depends whether the engine is off, idling or headed down the highway. You should be pulling 150-180amps depending on system voltage when the amp hits.

How long is the batt voltage at 11?

Check member "Gain-Mob" on here. He was doing a "little" upgrade on his expy using dual alternators and has threads on making/installing his system.

 

[2003FordGuy]

At idle my amp shuts down when the voltage drops down to 8 volts. I understand that the rpm is around 600 rpm and the pulley is stock, not smaller. But when I'm driving say 2,000 rpm, depending on what song I'm playing with bass frequencies around 80-120, the higher frets pull a lot of current which will shutdown my amp. That's at 2000 rpm cruising speed. But ill look into the post you mentioned Thanks man.

 

[TobyU]

Have dealt with a lot of limos and they often have 2nd alternator and battery so the entire rear stretch part is separate. Many are not though.
I have found that a smaller pulley makes a world of difference on the ones that are ok while driving but at idle or in traffic with it in gear they drain.

I have a town car and a couple of excursions here now that haw two alternators.
One of the excursions even has two compressors...that's a lot to fit in there even in an Excursion two alts and two compressors.
I prefer one compressor system BUT is is nice to not loose both at once and you hope if one goes out it will be the driver's front and not the passengers in rear.
The dual alts are very nice because they all have a battery backup switch so if one alt goes bad and that battery gets discharges you can at least finish the run or get it back to shop by holding the button down as it connects the tow batts together and as long as you are moving it will be fine.

I had some older ones with the 200 amp Lestek, Amptec, Powerline ones too.
Had one putting out 208 amps when cold.

A lot of the CB guys with big linears had to do bigger alts and multiple batteries for the load they draw.

Sometimes you can get by with two batts for shorter term loads but if a stereo amp that is pulling amps for a good while...I think you will need more amps from alt too.

 

[1955moose]

You've got one serious amplifier there at 2300 watts. That's the highest I've heard of for an Auto. You need to run a dual battery setup like Toby stated. Interstate has some humongous deep cycle batteries available. I saw one that was like 3 feet long. It gets mounted in the rear with long heavy duty cables. As Stamp stated your alternator is only going to charge just so much, the voltage regulator will see to that. I'm surprised you or the shop that installed this Godzilla of an amp, didn't install the total package. You wouldn't drop in a 600 horsepower engine into a car/truck, without brakes to stop it! Look into the dual battery setup with the isolater. And of course the bigger alternator.

Sent from my N9131 using Tapatalk

 

[TobyU]

You wouldn't drop in a 600 horsepower engine into a car/truck, without brakes to stop it!

Well, you shouldn't but some of us have...

 

[2003FordGuy]

You've got one serious amplifier there at 2300 watts. That's the highest I've heard of for an Auto. You need to run a dual battery setup like Toby stated. Interstate has some humongous deep cycle batteries available. I saw one that was like 3 feet long. It gets mounted in the rear with long heavy duty cables. As Stamp stated your alternator is only going to charge just so much, the voltage regulator will see to that. I'm surprised you or the shop that installed this Godzilla of an amp, didn't install the total package. You wouldn't drop in a 600 horsepower engine into a car/truck, without brakes to stop it! Look into the dual battery setup with the isolater. And of course the bigger alternator.

Sent from my N9131 using Tapatalk

I installed 2 yellow top Optimas, 0 gauge amp kit, new 135 Duralast Alt, a 250 amp battery power isolator.

 

[2003FordGuy]

Big 3 Upgrade with dual battery setup.