What are you folks using for a high outout alternator in your hotrods?

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Jeremiah (jd)

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My roundback Powermaster 95A alternator bit the dust and is beyond the (rather short) warranty. I'd like to go 130+ amps, single groove V'belt pulley with an internal regulator.

I'd also like to retain the original brackets if possible. The engine is currently wearing a set of 440 Source Stealths that will eventually be replaced with a set of Indy EZ -1s if that helps.

Please share your recommendations and other experience if you don't mind.

Thanks, jd

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I don't need high output. I am taking the big stereo out with the subwoofer and no electric fans. What are you running that needs so much power?
 
I have bypassed the ammeter. In addition, there's a 12 circuit fuse panel with multiple relays under the battery tray. Only the interior lights, turn signals, brake lights and dome light go through the bulkhead connector.

I have the following electrical components to feed:

N20 solenoids
N20 progressive
MSD 7AL2
O2 sensors/AFR meters
Dual electric fans
340 LPH fuel pump
(Future) electric water pump
Electric exhaust cutouts
(Future) EFI ecu
(Future) EFI dash
Lights
Line lock

I'm thinking 130-165A should be plenty. I'm leaning towards this:

Powermaster 8-68529-116 Powermaster Street Alternators | Summit Racing
 
I’d just buy the brackets/pigtail setup from AR engineering, and run a “john deere 100211-603“ 120amp little denso alternator. Saves some weight/space.

I run a 90AMP denso style in my street car. Aeromotive eliminator pump, two fans, lights, digital dash, 6AL2, wideband, etc. it does just fine and is the only thing I found that’ll fit.

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when I had my R/T I EFI'd the 505" and used a cs130 , just replace the serp. pulley with a GM v-pulley. buy the GM plug with the resistor built in to trigger (sense) and an 8ga wire to the battery post on the starter relay. Stock brackets and easy part store availability. ACdelco3351031 1993 Buick century 3.3 with a generic chrome gm alternator v-pulley for a 12si. I did this in 2000
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I run a 150A Powermaster single wire. All charging wiring upgraded. Today i would run a double groove pulley, so i could run it with less dension to increase bearing life from waterpump
 
My roundback Powermaster 95A alternator bit the dust and is beyond the (rather short) warranty. I'd like to go 130+ amps, single groove V'belt pulley with an internal regulator.

I'd also like to retain the original brackets if possible. The engine is currently wearing a set of 440 Source Stealths that will eventually be replaced with a set of Indy EZ -1s if that helps.

Please share your recommendations and other experience if you don't mind.

Thanks, jd

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Power master makes them up to 200 and something amps.
 
I’d just buy the brackets/pigtail setup from AR engineering, and run a “john deere 100211-603“ 120amp little denso alternator. Saves some weight/space.

I run a 90AMP denso style in my street car. Aeromotive eliminator pump, two fans, lights, digital dash, 6AL2, wideband, etc. it does just fine and is the only thing I found that’ll fit.

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They make a double pulley too.
Pardon Our Interruption...
 
I like the idea of moving it to the passenger side. The drivers front corner of the engine is pretty busy with the fuel system and all of that junk.
 
100 amp GM one wire mounted on the power steering bracket. Run the wire to your main 12V source and that is it. I use a solenoid to shut it off in the water box before a run.

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100 amp GM one wire mounted on the power steering bracket. Run the wire to your main 12V source and that is it. I use a solenoid to shut it off in the water box before a run.

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I use the micro switch on my carb and a normally closed relay. It charges at all times except full throttle.
 
+1 on the small denso. I run EFI, dual fuel pumps, dual fans, water/meth injection pump, and a few other gadgets plus headlights and still have some overhead on mine. I think it’s a 100amp model.
 
Powermaster 150 amp 1 wire
13.5-18.5 volts adjustable regulator. 8148 part number. Puts out I think 60-65amps at idle and little over 150 full throttle. Not that it ever needs that many amps. But the smaller units don’t charge enough at idle to do the job.

I run a 16v battery so I have it turned up to 18.5 volts. Charges great. I don’t need to charge at the track on race days.
 

You guys put so much good info into this thread that I'm looking at a full blown re-engineering project.

I'm very thankful to all that took time to share thoughts on the subject.

I think at this point my plan is to use a Denso alternator on the passenger side and experiment with a microswitch for WOT cutout. In the short term I ordered another 95 amp powermaster so I can stab it in and get this thing to the track for some quarter mile therapy.

Much appreciate all of you input!
 
It's not how much the alternator will put out max, it's how much it puts out at idle. If you have your w/p,dual fans, fuel system, Ignition (like 1 amp per 1000 rpm) lights,wipers ,blower motor if you've got that,you need to add up there draw. if you're alternator isnt putting out what is being drawn you will kill your battery. I have a Power Master 180 mounted on a motor plate and it does like 80 amps at 1200 rpms. BTW a good cooling fan motor will draw like 40 amps....
 
That's a very good point concerning idle output.

I do not have issues with the system as it currently operates with the 95A unit. I was hoping to upgrade to an electric w/p which initiated this inquiry.

The heater and wipers are inoperable so no worries there. Once I get this show on the road I will put my amp probe on the power wires coming from the alternator and report back. Empirical data rules the world as we have discussed many times.

As a side note, my n20 bottle heater runs on a Milwaukee M18 battery controlled by a pressure transducer so no draw there. This is one of the best electrical system upgrades I have ever done to a car with a nitrous kit.
 
That's a very good point concerning idle output.

I do not have issues with the system as it currently operates with the 95A unit. I was hoping to upgrade to an electric w/p which initiated this inquiry.

The heater and wipers are inoperable so no worries there. Once I get this show on the road I will put my amp probe on the power wires coming from the alternator and report back. Empirical data rules the world as we have discussed many times.

As a side note, my n20 bottle heater runs on a Milwaukee M18 battery controlled by a pressure transducer so no draw there. This is one of the best electrical system upgrades I have ever done to a car with a nitrous kit.
That’s a pretty cool setup for the bottle heater.
 
I had a 100 amp mini grapefruit size alternator and didn't realize it was only putting out like 20 amps at idle......by the late afternoon at the track the starter would just click.
 
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