|08-25-2012 03:28 PM|
About a month ago, I did the headlight relay conversion. I run a 1-wire alternator, so I hid the new headlight relays in the old voltage regulator casing. Note that in GM fashion, this taps off the horn relay that receives its current directly from the alternator.
Using the photometer in my Nikon, I estimate that this conversion made the low beams 100% brighter and the high beams 66% brighter. Others report similar increases. This also takes a load off of your dash lights and they too get brighter.
|08-25-2012 03:07 PM|
|JeffB||There is something that a lot of folks miss and that is the use of relays when doing a rewire this explains it well: Custom Cars Classic Hotrods Streetrods-Watsons StreetWorks Here in the archives of hotrodders.com are many articles by the late Doc. Vette who helped me out a while back.Two places you never want to run without a relay is an electric fuel pump and an electric fan(these draw a large amp load),a common complaint with older cars is dim headlights even though they have been halogen upgraded.I added the relays as per the link and WOW! major lighting improvement!|
|08-24-2012 02:55 PM|
Funny, I was just reading this Catalog last night.
It is worth the read. Mark at MAD Electrical really knows his stuff.
|08-23-2012 12:08 PM|
Take your power off the "always hot" horn relay contact. That's where GM used to do it.
|08-22-2012 08:50 PM|
Put in a distribution block just like this...
and you will be golden... Very simple. Pull your power from the alternator just as you were planning.
|08-22-2012 06:40 PM|
Not trying to cause a row, but I really don't see the common lines being any more that a buss, that is why I originally posted this topic.
How does the item know where it is at on the buss, it doesn't usually except for negligible resistance of the buss? If you draw a line (buss) and tap off for the battery, the starter solenoid, the alternator, and the take off for the fuse block, and then subsequently drew another line with a mix up of the location of the take offs, how would the buss be any different electrically?
|08-22-2012 04:14 PM|
Well to follow up on this I contacted Bob at Rebelwire and learned that my harness was mislabeled. Apperantly someone installed an "Alternator +" lead where they should have put a "Solenoid +" lead. What this means is I have to spend time re routing my harness this weekend. It's a pain because I maticulously group, wrap and shrinktube all my wires at exact lengths so I will need to cut the wire out to re route. To make things more difficult I use high end adhesive lined shrink tubing on many of the wre groups. Not easily removed.
This is kind of a PITA. I did much research before buying my wiring kit and I had heard so many good things and not a single knock aganst rebelwire. Well, here's the first knock against them.
|08-21-2012 08:53 PM|
The new wire kit I just installed came with wiring to run a 10g jumper with fusible link from the starter solenoid post to the battery lug on the alternator. From there another 10g lead goes from the alternatorlug to supply power to my main fuse panel in the cab of the vehicle. Are you saying running the power wire from the alt to my fuse panel is wrong?
By the way it is a rebelwire 9+3 kit.
|12-27-2011 08:55 PM|
why dont u just run a wire from the wiper ignition hot lead to a relay then to ur fans ur making this more complicated than it is.u can also use that for ur headlights.then u can run a switch in ur car also to run the fan,thats what i did.
|12-27-2011 05:07 PM|
|12-27-2011 03:58 PM|
Pretty sure that if it takes 16 volts at the alternator to get to the battery with 14 volts something is indeed wrong. I'm willing to stand by that. Something is wrong for a 2 volt drop, should be always be definitely less than 5% (or even better 3%) of applied voltage.
Also stand by this: The voltage drop to the battery from the alternator will surely be less than 1/2 volt. (less than 3%)
Pretty sure that they are both correct, and follow with current flow, with properly sized cable and adequate components. The alternator would indeed be producing a higher voltage than the battery.
Sorry if I didn't explain this in a better fashion in my earlier post.
|12-27-2011 02:59 PM|
"I understand voltage drops."
"If you have to output 16 volts to get 14 to the battery, something is wrong. Not sure why you are bringing that up."
I am going to politely suggest that you do not understand voltage drop, if you cannot understand why you would need an alternator to put out more voltage than you get at the battery with current flowing.
|12-27-2011 01:30 PM|
Not sure where everyone is going with this.
The alternator supplies all the voltage when the vehicle is running, as well as sufficient to charge the battery.
If you have to output 16 volts to get 14 to the battery, something is wrong. Not sure why you are bringing that up.
It is a 3 wire alternator, so I can put the sense point anywhere.
I understand voltage drops. That's why it makes more sense to run the coolant fan/headlights from the alternator, rather than from the battery at the rear. When the car is running, the alternator is the voltage source, not the battery. The voltage drop to the battery from the alternator will surely be less than 1/2 volt.
Please explain why it is better to run the front fuse block from the battery, rather than from the alternator, when all 3 items are in parallel. How would it be different?
|12-27-2011 12:17 PM|
What kind of alternator are you using? How is it wired? Is it a GM "single wire"?
The most important function of the alternator is to keep the battery charged. If the battery is dead, you cannot start the car, so cooling the engine becomes unnecessary, and if you are not driving the car, you do not need headlights.
OK, you knew that already.
With a remote battery, the issue become getting the right voltage and current to the battery, in the trunk. Every wire has resistance, even 4-0 gauge cable. The alternator has to put out more voltage than the "ideal" voltage needed at the battery to charge the battery. Depending on the wire (or cable size) the alternator may need to have around 15 or 16 volts AT THE B+ TERMINAL ON THE ALTERNATOR to get 14 volts at the battery. This is called voltage drop. Consider the ground side of the alternator wiring also. Especially with the trunk mounted battery.
One thing people do not realize the battery also functions to regulate the voltage, for a while. When the battery is electrically close to the alternator, the battery is able to better control, or damp any voltage spikes made by the alternator. With a remote battery the voltage at the alternator will vary more. it you start the car, and drive it at night, I could see a situation where the alternator is trying to charge the battery, and puts out 15+ volts to bring the battery up to charge, and you are also running the excess voltage straight to the headlights. They will be really bright. For a short period of time.
If you are using a "one wire" alternator, the alternator does not really know what the battery voltage. The internal regulator only knows the voltage at the B+ terminal of the alternator. Your battery will be most likely be slightly undercharged.
When you are done with wiring your car, you will need to check the voltage drops in the charging circuit, and probably the starting circuit. It would be a good idea to check what the voltage is at the headlights, also
Here is a web page that explains checking voltage drops much better than I could, and it is already done.
|12-27-2011 08:24 AM|
vicrod,thank you for your response. You are correct in what you are saying. However what you described is not what is proposed.
There would be two wires, one running from the alternator to the starter solenoid to act as the battery charge (and feed for the primary fuse block), and a second wire from the alternator to the fuse/relay block at the front of the car for the coolant fan/headlights. There would be two wires, each #8. Overcurrent protection could be fuses, or fusible link.
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