Current Draw from headlights

karolko

Well-Known Member
Joined
Sep 18, 2007
Has anyone ever tested or knows how many amps our regular headlights draw for amps? I am talking about regular glass Silvania's.

I am planning on rewiring the front clip wiring and knowing the draw will let me choose the proper gauge wire.

Adrian
 
The main drop in voltage seen in our cars is through the C-100 wirewall block, which i am completely eliminating, along with the old fuse panel, With that crap gone, you will not really need to "Hot Wire" the headlights as long as the fusepanel and light switch have good wiring to and from them.

I went onto the Silvania webiste and found that the headlights draw 55watts at 12.8 volt which equates to 4.3amps, and 3.9amps at 14 volts. What i am stumped about is that there is a primary and secondary filamnet named in the spec sheet...what is that about, when our low beams are on isn't there only one filament on, or is there actually two? Also i can't remember but when you put the high beams on do the low beams turn off entirely?


Nowhere near the car to test it out.

Adrian
 
so both filamnets are on during lowbeam operation correct?
When you turn on the high beams, the lows go off, correct?
 
One filament is on for low beams. When switched to high the low filament goes out and the high turns on.

Both filaments don't run at the same time.
 
FWIW, don't try to run both the low and the high in the outside bulbs at the same time. You'll overheat the bulb and the wiring.

It's not worth the extra light you'd get. You want good lighting, go for the HID kits out there and never look back. You will need relays however. The startup current on HID's is too much for our factory headlight wiring to keep up with, even though the full-on current consumption is lower than the filament counterpart.
 
Thanks guys, I never knew that when operating on high beams that all four lights were on, i always thought it was one or the other.

I am going to stay away from the HID's mainly because i do not do too much night driving and this is mainly a racecar that sees the street to scare the coppers backinto the donut shops. That and i don't want the look of HID's on the car.

Adrian
 
With HID's on your daily driver, you get used to them real fast. The older you get, the better that high intensity headlight beam looks ;)

Careful selection of HID's on your GN will avoid the ricer look, and just appear to be nice white light. No more than 4000K and you're good to go.
 
With HID's on your daily driver, you get used to them real fast. The older you get, the better that high intensity headlight beam looks ;)

Careful selection of HID's on your GN will avoid the ricer look, and just appear to be nice white light. No more than 4000K and you're good to go.
FWIW, don't try to run both the low and the high in the outside bulbs at the same time. You'll overheat the bulb and the wiring.

It's not worth the extra light you'd get. You want good lighting, go for the HID kits out there and never look back. You will need relays however. The startup current on HID's is too much for our factory headlight wiring to keep up with, even though the full-on current consumption is lower than the filament counterpart.
Any suggestions on a good quality kit to avoid the ricer look?
 
Not sure what's out there. You should start with quality H4 low beam lamp housings, then go for the H4 conversion. There are some very cheap Chinese ballasts out there that are actually not too bad - I've used a few of them (buy a pair as a backup anyway) and look for H4 direct install arc bulbs with the correct shield, and don't opt for anything more than 4000K temperature. If you go higher, the light will appear too blue. When I supplied the Philips kits years ago, I used 3800K Westinghouse D2S bulbs, a custom shield/carrier, and the OEM style ballast. The Westinghouse bulbs have a minimum of 3000 hours of MTBF life, so they'll last the life of the car though I'm not sure if they are even available anymore. I stopped supplying that stuff years ago, although the shield is still available:
http://www.casperselectronics.com/store2/product_info.php?products_id=693

Look to Ebay for the HID ballasts and D2S 4000K bulbs and you should be good to go. I might have a few bulbs left, but definitely no more ballasts. I have had HID's on my Cobra since 1996 and still the best lighting available.
 
Alradco kit is very nice.
Steve, is there a distinct cut off line at the top of the beam? For example, if the car is 20 feet from the garage door with the lights on, is there a nice straight line from the lights at the top of the beam pattern?

Rob
 
Top