GTV6 headlight conversion relay

Giorgio68 · #1 (**permalink**) 05-13-2008, 05:35 PM

I am in the process of replacing the sealed beam headlights into Hella H4, H1 halogen headlight.

I would like to ad some relays, has anyone done this other than (hiperformancestore.com), I would to know the process what type of relays to use and the whole procedure, so I can get enough voltage to the headlight before burning anything on the system.

I did a quick test with the voltmeter I am getting 13.5V on the alternator vs 11.7 on the headlight.

Giorgio

al_cam · #2 (**permalink**) 05-13-2008, 07:42 PM

Giorgio,

Electrics for cars are usually designed to run at the alternator volts 13.5v - 13.8v, so you're not going to burn out the globes. You need to select a relay to handle the current the globes will draw. Watts as used by the globes is volts x amps, so divide your total amperage by the volts and get a higher amperage relay. Use one relay for both globes, so multiply the watts by 2. For example 150 w globe? 150x2=300W, 300w/13.8v=21.8A. You need a relay that handles more than that. Typical car relay is 30A. Although if you are getting close to the rated current for a relay, they tend to get hot and melt. If you were using globes higher than 150W each you'd be better off using one relay for each globe.
Al Campbell

**alfaparticle** · #3 (**permalink**) 05-14-2008, 04:41 AM

There is an ebay seller that has sets of 4 relays for about $15. I have them installed on my Milano for E code lights.

**GreyGTV6** · #4 (**permalink**) 05-14-2008, 10:53 AM

I'm about one month away from doing mine. From my planning it should be a fairly painless job. On the L/H bulkhead there is a direct feed from the battery that could be fed into the relay while the original feed to the lights will be used on the coil side to pick the relay. I would like to find some fuses to mount to the bulkhead rather than use loose in-line relays. I have new head lights so I'm keeping them stock because I feel with proper voltage and grounding they should suffice. Please keep us updated and post pics if possible.

I cleaned my tail-lights and polished the reflectors of one to compare the difference with my other light and the difference is dramatic. The L/H light is bright and crisp, while the R/H is dull as you would expect from a 20 y/o car.

Steve.

Giorgio68 · #5 (**permalink**) 05-14-2008, 11:15 AM

Quote:

Originally Posted by al_cam

Giorgio,

Electrics for cars are usually designed to run at the alternator volts 13.5v - 13.8v, so you're not going to burn out the globes. You need to select a relay to handle the current the globes will draw. Watts as used by the globes is volts x amps, so divide your total amperage by the volts and get a higher amperage relay. Use one relay for both globes, so multiply the watts by 2. For example 150 w globe? 150x2=300W, 300w/13.8v=21.8A. You need a relay that handles more than that. Typical car relay is 30A. Although if you are getting close to the rated current for a relay, they tend to get hot and melt. If you were using globes higher than 150W each you'd be better off using one relay for each globe.
Al Campbell

ToonRboy · #6 (**permalink**) 05-14-2008, 11:46 AM

I bought mine from "paylesstellfriends" on ebay. eBay Motors: FIAT / ALFA ROMEO HEADLIGHT RELAYS , You'd be surprised at how much brighter the stock sealed beams get just by installing relays (at least on the GTV6). Nice clean voltage going to the headlamps rather than through all the oxidized connections in the steering column. I may swap to H4/H1's, but I just installed fogs under the bumper on another relay to help in those rural stretches... Daniel Stern Lighting has a couple of nice diagrams. Relays: WHY AND HOW TO UPGRADE YOUR HEADLAMP CIRCUIT

jjeffries · #7 (**permalink**) 05-14-2008, 01:59 PM

Google "Daniel J Stern Lighting Consultancy"; he has exactly what you needs at a very reasonable price, using highest quality european relays and clear instructions.

Giorgio68 · #8 (**permalink**) 05-14-2008, 02:33 PM

Quote:

Originally Posted by jjeffries

Google "Daniel J Stern Lighting Consultancy"; he has exactly what you needs at a very reasonable price, using highest quality european relays and clear instructions.

al_cam · #9 (**permalink**) 05-14-2008, 03:15 PM

Giorgio,

That'd work fine except I'd put a second fuse in for the low beam lights, in the red wire, taking it back to the battery positive. That way if a fuse blows, you don't loose both sets of lights. Also in that case you've got four high beam globes going through one relay and one fuse, so rate your fuse accordingly.

Al.