Hi Amp Alternator
 

Hey Guys

I am looking at upgrading my alternator over the winter, I have added a pile of audio in the boat and would like something that puts out more than the stock [55amp?] alternator now. I know some of the "car stereo" guys use hi amp alternators and "mini alternators" Does anyone make a high output marine alternator, I am looking for the most amps I can get. My boat is powered by a single 454EFI and uses a V belt to drive the alternator.

I have seen a few "car" alternators that use a single wire, my alternator has 4 wires coming out of it, I have been told 1 of the wires in for the tach, but, not sure? Can I use a single wire alternator? I am open to using a reoworked "stock" style alternator, or an aftermarket one, but, it must be a Marine alternator.

Thanks!
Michael

The Tach wire comes off the neg side of the coil.

I hope you've added a battery or 2 for the additional stereo stuff. If not, you need to. Make sure to use a marine grade alternator that has spark protection. I know there are marine alternators that put out more than 55 amps, but not sure where to get them.

My 105amp marine alternators are from dbelectrical.com

Thanks!

Yes, I currently have 4 Optima Batteries, 2 for starting and 2 for the stereo, they are hooked to 2 Battery disconnect swtiches [set up as "banks"] I also have a on board charger and I used good cables/connectors in the install.

If the tach comes off the neg side of the coil, what do the other wires from the alternator do? There are 2 red wires [1 large and one small] and 2 black wires [1 large, 1 small] I assume the large red is "Power" and the large black is "Ground" Any idea what the smaller red/black wires are? and could I use a "1 wire" set up without a pile of work?

Appreciate the Input Thanks!, Will check out the link and see what they have to offer!

Michael

We have several options for you from the traditional 55 & 94 all the way up to 120amp. Let us know if we can help.
http://www.cpperformance.com/SearchR...anufacturer=47

Thanks!

I think that I will go with DB Electric, they offer a 140 amp marine model, thats quite affordable [Thanks "Blue Thunder"!] but, I will Email CP soon, I need new Gauges for my boat and would like to go to the Auto Meter marine carbon fibre style, THANKS!

Michael

Ohio Generator makes them as well. Be sure to check the power curve as most alts need rpms to make power. Alot of alternators will make the same charge at idle so if your just trying to start your boat and charge your batteries they may not work any better than stock. If your running WOT they work much better. Just a lesson learned. I wouldnt spend the money with out doing some additional research or you might have spent your $$ for no reason.

Thanks Anchor!

That IS something I checked out actually, the 140amp unit I looked at puts out 85 amps at "idle" and full amperage at 1200 RPM, so, I am thinking even at a "slow" cruise I should be getting plenty of power. I will check out Ohio Generator and see what they have, I talked to a kid that lives up the street from me that has one of these "rice burners" with about 150 speakers in it, and he runs a 200 amp alternator, but, its not a marine unit, I was suprised how small it was though! I think it was a "Powermaster" or something like that.

Thanks!
Michael

If you can find someone that really knows about the batteries you have you may check with them as well as some batteries can only charge so fast. Has to do with the amphours of the batteries if I remember correctly which with the number of beers I've had since I put one on my 25 may not be much. :drink: I know that you can spend a pile and not get the results you want. If the batteries cant take all the charge then well your spinning your prop for nothing. I know when I did it i went with a 120A alt as anything bigger was wasted. I carried 2 100AH batteries. Here is a good battery site. The guy that runs it is very knowledgeable. http://www.ebatteriestogo.com/Trojan..._Batteries.htm

I know your not looking for batteries but you might talk with the guy about how much and how fast a battery can take a charge. You might check it out.

Will

LOL@ Beers!!! Thanks Will!

I have 4 Optima Marine batteries now, will check the amp hours rating on them, Will check out the website too! Thanks again, I spoke with a fella today who claims to be safe you should have 70 Amps for every 1000 Watts, now, he said that would be for 1000 "real" watts, not the 1000 Watt Amp you buy at Wal Mart for $29! LOL! So, I am looking at around 200 Amps to be "safe"

Will see whats out there and do some more research, thanks again for ALL the help!

Michael

I bought 2 Ohio Generator Alternators a few years back and they claimed 280 amps on test sheet. They put a smaller pulley on them to make them spin faster, but still require 3000 rpm's and above to reach full amp capacity. These don't work the greatest for the money spent in a marine application. I'm still working with them to get them to charge full capacity at around 1200 rpm's I'll keep you posted. I'm running 3 Optima blue tops and 2 Kinetic Monsters 1200's I'm pushing close to 3000 watts of amps though. Damn no wonder my boat keeps slowing down every year.

WOW!, Thats some SERIOUS Audio, must sound KILLER!

Just curious what you would recommend for an alternator for my application? Thanks!

Michael

Sadly for the marine application Ohio Generator seems to be it, but they can't get it to charge at lower RPM's which most of us seem to need it to charge around 1000-2000rpm's and be at full capacity. The best I've seen is 120amp alternators you sound like your in the same boat as me needing 200amp or more. Only thing I can recommend is to take your stock alternator to a shop and tell them to make it put out the most they can.

How many Farad capacitor are you guys running?

You need approx 1 Farad for every 1K watts, I have heard different opinions, some claim that IF you have enough battery power [multiple batteries] then they aren't work the effort, I have also heard people say they make a "huge" difference. There might be others on here with more knowledge/experience.

I have seen many SERIOUS marine audio systems that didn't t have them though.

Michael