voltage stabilizers, waste of money?

[1967stang302]

Ok, so when I start my 67 mustang, the headlights brighten when I rev the engine and die down when I let it idle. I have talked to my mechanic who says he switched everything out and it is just the way it works stock, so I'm not going stock, I'm going serious retro mod. And there will be a lot of electrical toys I'm installing and I know that variable voltage can damage some of the electrical equipment I'm installing. I am putting in a 120AMP alternator and probably a red top battery after some time, but I want to know if I should toss in one of these E-bay special voltage stabilizers? And if I do, would I still need a capacitor for my stereo since these stabilizers are pretty much a few caps in succession? any tips would be appreciated. If your wondering what I'm putting in, I'm adding a Voom PC with a gps and removable USB harddrive to store my music on to take home and in the car. I'm a total computer geek by the way.

 

[mdjay]

Common problem. You just need to run relays in front of your headlights...
http://www.mustangdepot.com/OnLineCatalog/images/Electrical/md-hlk.jpg

 

[66HertzClone]

Check and make sure there is a ground cable from the engine to the chassis. There should be one located on the rear of the right side cylinder head, this is often removed and or broken. Not having this cable will cause the symptoms you describe, tough to get a good electrical connection thru those insulated engine mounts.

 

[Tim65GT]

If you replace your alternator with a 120 amp your problem will go away.

Your issue of lights dimming when idling is because the stock alternator doesn't put out much at idle. If you run new type halogen lights, upgrade your wiring with relays to feed the power to them.

Here is a site:

http://www.humanspeakers.com/audi/headlight-simple.htm

OK...its not a mustang, but you can get the idea.

 

[5.0ina66]

Try an electronic voltage regulator from autozoo
Wells VR767 $10. The points-type surging regulators can spike with rpms whereas the electronic units will stay steady 12V

 

[ForceFed70]

A $10 voltage regulator will not fix the problem.

This is common in older vehicles. Like Tim65GT said, the older vehicles don't put out much at idle.

Swapping in a newer alternator would help. I suppose you could also move to a slightly smaller alternator pully (overdrive pully).

Take it from someone who owns one of them fancy $120 stiffening capacitors.... they arn't worth it. These things are only good for guys in SPL compititions who only play a single tone for a split second. Your money is much better spent on alternator and/or battery upgrades.

 

[mdjay]

Actually the headlight relays, our kit or not, is a good fix for the dimming headlights. The headlights are a "last in line" in terms of getting the power since it has to run from the ignition, through the underdash harness, through the headlight switch, and then through your headlight wiring harness. These cars are also very tough on grounds so check your grounds, and run extras!

Most of us are trying to add all kinds of components including stereos, hid headlights, fog lights, electric fans etc, etc into small old crusty wires that can't run that kind of current even new. You can get the big alt, it works good but not at idle as stated. You will have to overdrive it to make it work at idle. If not, you just beat up on batteries. I agree on the solid state regulators are much better than the point driven units, but it's not a fix for too much draw on an atiquated charging system.

Everyone here has helpful comments on upgrading the components of your charging system to run your goodies. It's just tough to point your finger at one thing since you're only as good as the weakest link in the entire system.

 

[Tim65GT]

Originally posted by Mdjay:

Actually the headlight relays, our kit or not, is a good fix for the dimming headlights. The headlights are a "last in line" in terms of getting the power since it has to run from the ignition, through the underdash harness, through the headlight switch, and then through your headlight wiring harness. These cars are also very tough on grounds so check your grounds, and run extras!

I put Sylvania Silverstar Halogen Bulbs on mine and it started flickering off because of the Circuit Breaker in the headlight Switch.

I installed the "headlight relays", which stopped the headlights from turning off - on - off, but they still went dim at idle. The alternator was only putting out about 12 volts at idle and 13.5 when reved up.

When I upgraded to a 3G alternator...problem solved.

 

[bnickel]

if you want a more modern alternator but want to keep a somewhat vintage looking engine bay you can run an older gm internally regulated alternator. you should be able to get a 100 amp unit from any parts store for about 50 bucks or less. there will be a little bit of wiring to do but it should be easy enough.

 

[mdjay]

Originally posted by Mdjay:


I put Sylvania Silverstar Halogen Bulbs on mine and it started flickering off because of the Circuit Breaker in the headlight Switch.

I installed the "headlight relays", which stopped the headlights from turning off - on - off, but they still went dim at idle. The alternator was only putting out about 12 volts at idle and 13.5 when reved up.

When I upgraded to a 3G alternator...problem solved.

Like I said, it's tough to pin it down to one thing. If you like to run lots of peripherals, it's a good idea to go through your system and upgrade the system as a whole. Otherwise you're gonna be chasing your tail.

 

[ForceFed70]

Actually the headlight relays, our kit or not, is a good fix for the dimming headlights. The headlights are a "last in line" in terms of getting the power since it has to run from the ignition, through the underdash harness, through the headlight switch, and then through your headlight wiring harness. These cars are also very tough on grounds so check your grounds, and run extras!

Actually it will not fix his problem.. although it may result in brighter headlights overall, it won't stop them from dimming at idle.

They go dim because the alternator is not putting out 14 volts at idle... it's dropping close to battery voltage (12volts). No amount of relays or voltage regulators is going to make his alternator put out more power at idle.

Personally I don't see this as a problem. Generally when my engine is idleing, I'm not moving very fast and don't really need the headlights to be super-bright. Although I could see how it could cause a problem if your stuck in traffic for an hour and want to crank up the tunes.

 

[mdjay]

Actually it will not fix his problem.. although it may result in brighter headlights overall, it won't stop them from dimming at idle.

You would be surprised. It's not a cure all but it helps a lot.

It also depends on where his idle is set. If he's like me, I like it around 700-800 rpms so it's low and loapy. Not much I can do.

I have a 120amp alt, solid state voltage reg rated at 200amps, brand new wiring, battery is in the trunk with 0 gauge running front to back, grounds at the motor mounts, and the firewall. 0 gauge ground at the rear 2 ft long so it doesn't resistorize.

The only thing in line currently is the dual elec fan. Even without my stereo they will dim at idle. I have the stock pulley but I don't want overdrive it because this motor spins at over 7k.

For me, it comes down to getting more power right to the Halogen headlamps. It dimmed with the stock headlamps too...

Heck, you could probably run a capacitor ahead if it. JK

 

[Tim65GT]

Posted by Mdjay:

I have a 120amp alt, solid state voltage reg rated at 200amps, brand new wiring, battery is in the trunk with 0 gauge running front to back, grounds at the motor mounts, and the firewall. 0 gauge ground at the rear 2 ft long so it doesn't resistorize.

The only thing in line currently is the dual elec fan. Even without my stereo they will dim at idle.

A 120A Alternator should put out enough at idle (at least 40 amps) to handle fans and headlights.
Do you have underdrive pullies?
What is the voltage at idle with the lights and fan on?
What is the gauge of the wire from the alt to the bat? It should be 6 or 4.
Does the sense wire of the volt reg go back to the trunk also?

Posted by Mdjay:

Heck, you could probably run a capacitor ahead if it. JK

I'm pretty sure the purpose of capacitors is to keep the voltage up for VERY short period of time. (milliseconds) They became popular when Amplifiers where getting so large the current draw would exceed the capacity of the system, but only when the bass hit highs levels.

The use of a capacitor(s) (voltage stabilizers) will not help for a load with a constant draw like lights and fans. Just my $.02

 

[mdjay]

A 120A Alternator should put out enough at idle (at least 40 amps) to handle fans and headlights. At what rpm are you assuming 40amps?

Do you have underdrive pullies? nope stock

What is the voltage at idle with the lights and fan on? just a little over 12

What is the gauge of the wire from the alt to the bat? 0 gauge
It should be 6 or 4.

Does the sense wire of the volt reg go back to the trunk also? No/Yes that's part of the headlight harness which is connected to the alternator which is connected to the battery.

The system is sound. I have been doing this a long time and have a good handle on what works and what doesn't. I could just raise the idle a little and solve the problem but I like it down low!

The JK at the end of the capacitor statement stands for "Just Kidding." I know the function and use.

 

[Tim65GT]

A 120A Alternator should put out enough at idle (at least 40 amps) to handle fans and headlights.

At what rpm are you assuming 40amps?

Here is a web site where they tested a 3G and at 800 rpm got 75A!

http://www.fordmuscle.com/archives/2001/03/paperformance/index.shtml

So I was assuming...

posted by Bottlefed70:

Personally I don't see this as a problem. Generally when my engine is idleing, I'm not moving very fast and don't really need the headlights to be super-bright. Although I could see how it could cause a problem if your stuck in traffic for an hour and want to crank up the tunes.

If you're in traffic on a cold rainy night, you'll probably be using:
Lights
Wipers
Heater fan
Brake lights
Radio (if there is enough juice left for ignition)

I would want my system to perform best at idle.

After my 3G upgrade ($45 at a pick a part) the voltage stays above 13.5 at idle with all the accesories I can throw at it. i don't have electric fans ...Yet.

 

[mdjay]

Well mine must suck then