Where best place to get a bigger alternator for my '03?

With my upcoming system upgrades I don't think the 105 amp stock alternator is going to make it. I already think I am having issues when I have the seat heaters on, the headlights on and my fogs on with heater going full blast. Can't wait to see what will happen when I am running my computer and start upgrading my sound system... So I am looking to upgrade my alternator at this point. I would like to go with a 200+ amp alternator and have no clue what place to start looking for them.

I know from past training OEM alternators are rated cold for amps.. When warm most OEM alternators are more like half the rating due to losses in the system. Aftermarket alternators generally can put out significantly more especially if they use an external regulator. I HAVE a 130 hot rated alternator but it was for an LT1 equipped caprice and I don't believe it will line up. And with my planned up grades I am thinking a 200+ amp alternator would be a better choice.

I want to keep it stock looking so I don't need chrome or anything fancy.

Rodney

amazon

Take your pick....

http://www.summitracing.com/search/year/2003/make/chevrolet/model/avalanche-1500/department/ignitions-electrical/section/charging-systems/part-type/alternators-and-generators?SortBy=Default&SortOrder=Ascending&N=4294948138%2B4294951398%2B4294942844%2B4294951516%2B4294945625%2B4294944858%2B4294900042%2B4294866530%2B4294815729

Nations makes quality gear for the price.
http://www.nationsstarteralternator.com/Extreme-High-Amp-Output-Chevy-GM-Alternators-s/80.htm

If you want balls to the wall, certified power, DC is the way to go. they're one of the only manufacturers out there that guarantee output at peak and idle.
https://www.dcpowerinc.com/vafproducts/list?make=Chevrolet&model=Avalanche&year=2003&engine=5.3L+V8

I am running a nations 220A I bought a few months ago alongside a Delco 200A that I bought back when I had my 05.
I originally ordered a 250 from Nations, but when I tested the output at 131A at idle and 207A peak, I called and complained. They asked for the numbers off the case and when I provided them they said they sent a 220 by mistake and offered me a no cost return, but I opted for a partial refund since it was already installed. My Delco tested at 103 at idle and 180 peak. I never tested my stock alt. before I took it off.

if you need the most amps at idle DC puts out the highest out of anybody at 600rpm and ive looked at alot of alt companies. soon as im able to afford it thats what im going with.

oh yeah and i was bfowsing around and seen that tranny thread you had. that rc transmission in royal oak thatz the other side of detroit from me. but still good tokeep in mind for me if i need it.

Thanks for the suggestions!

Looks like DC power is the best solution of the ones posted and seemed to be reasonably priced.

Rodney

hey Rodney did you ever get an alt? I posted on chevy avalanche style on facebook, a guy who makes a dual alt braket. I'm not sure if you seen it or not. til 5-20 it's $20 off. so right now it's $200 and it comes with a new belt. so you could get another stock alt if you wanted and have 2 alts running either to the same system or different systems. it's nice thickness plate with tabs welded on it. I got mine today, and posted a pic on fb. you should check it out...... justa thought.

I have had other issues to deal with so I haven't upgraded my alternator yet. I HAVE a true 130 amp alternator that I can use as well which has true dual outputs. I need to see if it is compatible with the bracketing and if it is I might just use it.

Unless things have changed OEM alternators are rated for "cold" output and when warm (Like after 30 seconds) they only put out a portion of that amount. A standard GM 90 amp alternator only actually puts out 60 amps when engine is at operating temperature. I believe it is due to the efficiency of the components within the body. This aftermarket alternator moved the regulator to the exterior of the casing and is rated 130 amps cold and warm. So it should be almost double the output of my OEM 105 amp alternator even though it is only rated at 130.. I just haven't tried to see if it matches up. I bought it years ago for another vehicle.
If not then I will probably look at the bigger factory replacement alternator. The added cost of a second alternator is not beneficial to me at this point although I do have a second battery...

Rodney

HUH?
Cold hot rating?
where did you get this info?

IF GM says it is rated 130 amps and does not have conditions on this rating then it is good  for that all the time under normal driving conditions which would be hot..

Otherwise someone would have started a mass lawsuit and hit the press etc etc

Think back to Mitsibishi who overrated the HP of their engines... they had to ended up in court for that.
even with all the legalese about HP ratings in brochures.

I was informed by multiple sources in the early 2000's that the rating on a GM alternator (And probably others) is cold rating. That when warm they lose efficiency and the rating is not accurate. Since I did not keep notes I can't share where I heard it from but it is something to be aware of when looking at replacement alternators. Sort of like the wattage rating on an amplifier...

This can be the difference between buying a 140 amp OEM alternator and a premium after market 140 alternator. The premium one costs more but it likely actually puts out the rated amount at all temps... But again. Since I can't reproduce my notes to allow verification just be aware that the rating on an alternator is generally COLD rated and may not be the same as it is when warm.

(Ever wonder why an 18 or 16 gauge wire is sufficient to charge your battery from your alternator? But no where near enough to actually power your truck?)

Rodney