Need some suggestions for alternator and brackets. I prefer an externally regulated alternator.

I'll be running an electric fuel pump, electric fans, large stereo. Plus all the accessories and lights that a typical street car uses (all external lights, heater, interior lights) and possibly electric windows/locks in the future.

Its a street car and will be at idle a lot, not sure what I need for a minimum idle amp output.

I looked at the denso 120 kit from mancini, they say its a 3 wire and puts out about 65 at idle.

Mancini didnt think this would be enough for my application, and suggested the powermaster 170amp, #43311, but it will need a v groove pulley installed and they cannot confirm what brackets it's compatible with. The powermaster 43311 is a 3 wire and advertised to put out about 100 amps at idle.

What other options do I have?

The Mancini 120A kit is the only one that I know that would be a bolt on. Not sure why that wouldn't work for you. There aren't many cars that come OEM with anything bigger than that alternator. Even the full on luxury cars use 90 to 120 amp alternators and you aren't going to have power seats, heated mirrors, heated seats, etc. that you would find in a high end Lexus or Merc.

What Andy said, I've heard good regarding the Denso plus if it's pretty much the only bolt in, I'd pull the trigger on it. Make sure you have a regular (dia) crank pulley 7.25" iirc, not a smaller one. there are 2 diameters of OE alt pulleys, not sure which one the Denso comes with

Would the denso 120 be big enough run a stereo that had a 1000w amplifier?

you might call some of the local stereo shops & the right guy who has dealt with this before from a customer might be able to give you some sound advice on that. EDIT A shop that does actual installations

1000W at 12 volts requires 83 amps. But the duty cycle on a stereo amp is pretty low. They usually don't consume anything close to full power. Most guys add a second battery if they're going to run a big amp at max power for more than a few minutes at a time.

if its time to upgrade we have serpentine belt kits that use the dodge magnum engine alternators and you can get up to a 160 amp unit to fit on there.

If price is not a big concern try Mechman Alternators.

Supposed to be direct bolt on available in 150 or 240 amp with V belt.

http://www.mechman.com/alternators/dodge/1961-1979-vehicles/

I think flaming river resell their alternators.


Kevin

I forgot to mention the mechman 150 amp produces 100 amp at idle and has a 10 year warranty. It comes in either a single or double V belt.


Kevin

With AC? It matters. I went through this on a BB/Ed heads with AC which is hardest to retro-fit. Electronics, fuel pump but no electric fan. Stereo is the mechanical cam. The 140 amp small case GM (10 SI I think) based Powermaster would not clear the heads with Ed heads. Returned for credit (Summit). The best Powermaster square back at the time would and did run the car but big voltage drop at idle and running at max output continuously (75A) at night with brights and AC on. Voltage would hold pretty steady until I hit the bright switch then it would drop... charging but barely. I wound up using the old "big/giant Chrysler" alternator with brackets from my '78 Cordoba core engine. Charging performance at idle and speed is excellent but its heavy and I don't think it would handle electric fans very well. I had estimated max load at around 80 amps for my setup which came close +/- 5 amps. With electric fan you probably need 100-110+ amps to avoid voltage drop.

Suggestions are 1) big case GM/12 SI from Powermaster (may fit) or 2) One of the custom new square back high output replacements (Flaming River, Green alternators, maybe one other). 3) lose the electric fan & load and use a Denso 120. The high output square back replacements are spendy. Also suggest you measure head clearance with a square back for reference before placing the order for any of the above.

I called powermaster, he recommended I use this one. 100 amps at idle, 165 at cruise. Comes with v belt pulley and will work with stock brackets. Is this a 'big case GM'?

http://www.summitracing.com/parts/pwm-8-48529-120

Kevin those are really expensive. Is it the 10 year warranty that justifies the cost?

I agree they are very expensive !!! They are very proud of their product !!

I'm sure the price reflects the smaller mopar market, the billet case that makes it look very similar to a factory looking alternator and that it bolts up using factory brackets and of course the 100 amp output at Idle.

I currently have the mancini 120 A alternator on my car and I'm pretty sure I still get flickering lights at idle and I have headlight relays in place.

Kevin

Another alternative and cheaper than some of the others.

http://www.qualitypowerauto.com/item_557/Chrysler-Mount-Mega-Amp-Alternator.htm

"Big Case GM" would be the 200 amp version in the link attached (12 SI I believe). The Summit link looks like a newer "custom Chrysler case" style. Spendy but so is the 200 amp Delco derived unit.

Another consideration is drive belts. Rule of thumb, one belt is happy up to 100 amps. Sounds like you will need more than that for extended periods so may consider two belts.

Also, in non AC applications many have adopted original GM style big case alternators. May be worth getting a JY unit from a big Buick or something like that for test fit. That would be the only low cost option I know of.

http://www.powermastermotorsports.com/mopar_high_amp.html

The current drain can be significant if he is driving some subwoofers and pounding the bass...
However the highest current drain of accessories he has mentioned are the cooling fans, some of these can draw up to 75 Amps..

Just my $0.02..

Any car audio guy will tell you that if you are running a big amp, you should be using a capacitor (at least 1 farad) to help lessen the voltage dips on the electrical system from bass notes on the subs. This will keep you from seeing dimmed out lights that follow the music and lessen the load on the alternator. That will help significantly with the low duty cycle loads (like bass notes).