[blackmagik3]

Hey guys,

I have a '67 with a 383 and ls1 fans. Standard alternator. These fans pull a significant amount of current and when coupled with the headlights being on at night, the alternator performs less than great. As a result, the fans don't cool as well because they're not receiving the power they need.

Is a more powerful alternator the answer to this issue? Perhaps a power buffer? If so, what are the drawbacks of a more powerful alternator?

 

[ilikeike]

If you have a stock alt. It's most defiantly over worked with two fans,headlights,ignition,radio,wipers,maybe an electric fuel pump....
I went with a 140amp, I ordered a tuff stuff built alt.from jegs.
http://www.tuffstuffperformance.com/index.cfm/page/ptype=results/category_id=277/mode=cat/cat277.htm

And this may help keep your lights bright.

http://www.madelectrical.com/catalog/rly-1.shtml

 

[blackmagik3]

If you have a stock alt. It's most defiantly over worked with two fans,headlights,ignition,radio,wipers,maybe an electric fuel pump....
I went with a 140amp, I ordered a tuff stuff built alt.from jegs.
http://www.tuffstuffperformance.com/index.cfm/page/ptype=results/category_id=277/mode=cat/cat277.htm

And this may help keep your lights bright.

http://www.madelectrical.com/catalog/rly-1.shtml

Will I have to change anything else in the vehicle? From what I understand, amperage is the flow of current. With a larger alternator, I'm assuming it will actually output more power for the fans to consume, BUT will it deliver too much voltage to the other components by default?

 

[ilikeike]

It will deliver the same voltage.14.3v or so. Actually with everything running a doubt your stock one is delivering 14volts by the time it makes it to the dash harness.
Of course your wiring should be in good shape too. Your fans should already have the appropriate size wire and relays for the current that they draw.
You may need to upsize the charge wire to the battery.

 

[blackmagik3]

It will deliver the same voltage.14.3v or so. Actually with everything running a doubt your stock one is delivering 14volts by the time it makes it to the dash harness.
Of course your wiring should be in good shape too. Your fans should already have the appropriate size wire and relays for the current that they draw.

Each fan has it's own appropriate relay and the wiring is in good shape. I'm just trying to avoid making any costly mistakes.

 

[onovakind67]

Will I have to change anything else in the vehicle? From what I understand, amperage is the flow of current. With a larger alternator, I'm assuming it will actually output more power for the fans to consume, BUT will it deliver too much voltage to the other components by default?

Amp is the unit of current flow. Volt is the unit of electrical potential. Don't confuse the two. If your stock alternator produces 14v and your new alternator produces the same voltage, the same amount of current will flow to your components. The difference arises when the stock alternator is unable to keep up the 14v potential under the new current demands. Installing the new alternator will allow your system to stay at 14v even under the new current demands.

 

[larryh56]

If you upgrade you alternator it would be a good time to consider upgrading your charging system. I recommend you spend some time reading the upgraded system on the MadElectrical.com site noted above. You do not have to buy the kits from them but it is pretty handy because they provide you with everything you need and use quality materials. The headlight upgrade using relays makes a big difference.

 

[DOUG G]

I went with a CS130.
The one I bought was a direct fit minus the plug (very easy fix)
You will also need to do a little wiring at the voltage regulator (stock is ext. reg, CS130 is int. reg) Also an easy fix.

My fans, fuel pump, and lights all run without dimming at a stop light

A great read.....http://www.camaros.net/techref/ftecref14.html

 

[Everett#2390]

Very good info here.
You asked about too much power being generated - Ans. No.
The alternator will only supply the power demanded by the load upon it.

Tip: If you plan on rewiring the fans power source and headlamp power source, its easy.
Drvr side has the horn relay buss bar for power,
Pass side has the battery junction block for power.
The red wire from the alternator BATT stud should be swapped out for a 8 AWG to the horn relay and battery junction block. Solder the connections - wire brush the buss bar and apply a thin film of oil to it - its steel.

 

[onovakind67]

What is the particular reason for increasing the size of the battery charging wire?

 

[Everett#2390]

True, present wire size, #10 AWG, is okay, but, most OE wiring is rubber insulation vs. teflon insulation and one wouldn't want to see how much smoke GM, er, Packard, installed into the wire when OE insulation is at max capacity, i would think.

#10 AWG at 302°F is 60 amps
#8 AWG at 302°F is 76 amps

 

[onovakind67]

The needs of the battery don't change with the upgrade to the alternator. Once you have the car running it just becomes the same load it was before. If the quality of the insulation is a concern, how about the rest of the wiring in the car?

 

[Everett#2390]

True, the battery needs have not changed, its another parallel load - but I did not say to replace the fusible link to the battery - it still remains.

Since addition of fans, ease of wiring in power source for the physical location.
There may be the possibility of all circuits, if headlamp relay is added per lamp, and fans on at the same time - one fan per side, one headlamp per side, and recharge of battery, if OE design is kept in place, the #10 AWG running from alt BATT stud to buss bar could have as much as 80 amps or more, buss bar also supplies the rest of the OE vehicle harness, will do the job, but the heat given off due to wire internal resistance with large amount of current flowing may make it alittle hot. Install a bigger gauge wire making it 'cooler' and due to technology, better wire, read 'safer' as far as insulation, copper is copper.

Camaro could have A/C on with fan on high speed, all lights on, brake lights on, reverse lights on, hood, trunk, glovebox doors, a door opened, radio playing, maybe a power window, or all four being operated at the same time, auto trans in gear (lower alt RPM), and power steering being turned at the same time (lower alt RPM) - thereby lots of current flowing between alt BATT stud and buss bar. Did I leave any circuit out? Yes I did - horn.

As with the rest of the OE harnesses, I'm sure GM engineers did their homework in providing the proper gauge wire to load vs distance traveled and these circuits have not changed, as written here in this thread.

 

[BPOS]

^^I'm sure Everett said it above somewhere! The ideal place to connect your high current draw accessories (fans in this case) is the horn relay busbar. If you install an alt with higher output, you can leave the harness as is, and install an additional large gauge wire from the stud on the back of the alt to the horn relay busbar and avoid the nasty job of ripping the harness apart.

 

[onovakind67]

^^I'm sure Everett said it above somewhere! The ideal place to connect your high current draw accessories (fans in this case) is the horn relay busbar. If you install an alt with higher output, you can leave the harness as is, and install an additional large gauge wire from the stud on the back of the alt to the horn relay busbar and avoid the nasty job of ripping the harness apart.

Exactly. Connect your accessories to the highest potential.

 

[joesauer]

if you install a higher amp alt. & connect it's wire to the horn relay buss, don't you need a different gauge wire from the buss to the batt. also. Exampl= with a 100 amp alt, I should use an 8 gauge wire to the buss & maybe the batt.. With a 130/150/+ alt, think I should be using a 6 gauge (or maybe even a 4). Doesn't the higher gauge need to go all the way, not just to the buss. .......maybe need to install a circuit breaker & remove the fusable link.

 

[ilikeike]

if you install a higher amp alt. & connect it's wire to the horn relay buss, don't you need a different gauge wire from the buss to the batt. also. Exampl= with a 100 amp alt, I should use an 8 gauge wire to the buss & maybe the batt.. With a 130/150/+ alt, think I should be using a 6 gauge (or maybe even a 4). Doesn't the higher gauge need to go all the way, not just to the buss. .......maybe need to install a circuit breaker & remove the fusable link.

It depends on where your loads are hooked to.

The battery won't pull all those amps,an 8g or 10g is plenty to charge the battery, now if you have all your accessories hooked to it,then you'll need to upsize.

 

[SOA-Nova]

You have to keep in mind that even if you connect your fans to the horn relay buss and then have a new larger wire from it to the new larger alternator, what might happen if the fans are now getting power from the battery only through the original wire between the horn relay buss when the fans might be on and the alternator is not supplying power.

Another thing to keep in mind is depending on where the new fans are grounded and how much current they pull, you may have to upgrade some grounds or have the fans grounded to the motor.

Jim