[66GTO Jim]

I want to keep my original T-3 headlamps on my 66 GTO but would like them brighter. So I am looking at adding the relay setup and have a few questions I could not find answers for using the SEARCH function on this and other Forums. Sorry if this is long with many questions, but hopefully can gather some data here for folks searching in the future that have similar questions.

Plan on using the attached diagram (NOTE: 4 headlamp setup on 2nd page). I will wire my own system vs buying two pre-assembled (EXPENSIVE) kits.

Diagram found here:

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

Let me know if this sounds correct. In the attached diagram I will use corresponding GTO wire colors replacing the Audi wire colors specified. Cut the Black w/ Tan Stripe (low beam) wire and run one end to terminal #86 and the other end to terminal #87 on the relay for low beams. Cut the Black w/ Light Green (high beam) wire and attach to the same terminals on a 2nd relay for the high beams. Attach 12V (20 A fused) wires to the #30 terminals and then ground the #85 terminals as shown in diagram. This will be done between the radiator support and the headlamp bucket on the driver's side per recommendation on MAD ELECTRICAL website.

BTW the front wiring harness was newly installed just a few years ago, so wires and plugs should be good for T-3s and voltage, I hope.

NOW THE QUESTIONS:

- Where is the best source for non-switched 12 volt wire hookup on the front of the 66 GTO? (no horn relay in the front on a 66 GTO).

- Can both 12 volt wires be sourced from the same point or should they be hooked to different sources?

- Have read the Bosch relays are good for this. Does anyone have a part number I can use at NAPA etc? (BTW haven't visited a boneyard in years so prefer buying new)

- Does it need to be a weatherproof relay since it will be mounted outside the passenger compartment? If so do you know a brand and part number for the relay?

- Read where some suggest a slow-blow 20A fuse or a quick auto-reset circuit breaker. Overkill? If not what brand and part number for the circuit breakers?

- Some suggest replacing the headlamp plugs. Is this needed just for halogen etc or do I need to do it for T-3s also (remember, new wiring harness installed including new headlamp plugs)

Any help/answers appreciated! Jim

[Socrates]

Get power directly from the alternator, with power ran up front to your new custom fuse panel or inline fuses, then to your 2 relays.

Autoparts stores will have relays for sale near the headlight section, or ask for a relay from a 90's GM car, say a Caddy (if you have big $$ to spend for oem relays bought new, that is). If you really want BOSCH parts, the junkyard is ideal or the internet is your friend.

You don't need weatherproof relays, though they are nice. I've done it both ways, no problem with either. The new weather-tight BOSH relays with plugs are pretty pricey.

For the fuses or breaker, again, just go to your favorite local auto store. Fuse, breaker or fusible link is all personal preference. I chose a Fuse, though would use a breaker if I had one in my box too. Wouldn't touch a fusible link, personally.

You don't need new headlamp plugs, though it makes this upgrade easier and you don't have to hack into your factory harness at all. All of my cars have the factory harness entirely uncut. I use the OEM plugs as power sources to trigger the relays by inserting a male spade connector in the top and left prong (to #86 on your relay), and wire the power to the new plugs with nice 12 gauge wire (though 14 would more then suffice for T3s...).

Since you seem unwilling to hit a boneyard or scour the net for the parts, I'd suggest you give madelectrical your money and just use the kits they offer to make this work, as it will save much time and frustration in the long run. It's a super easy upgrade, so don't sweat to much over the minutia. Also, the remade T3's reportedly have much higher output vs originals, so if you really want more light it would be a good option, as the original T3's just are not going to be all that impressive, with relays or not..

[66GTO Jim]

Thanks for the detailed response, Socrates. Just what I was looking for.

BTW I have used the MADelectrical.com webiste many times as a reference but never I ordered anything. It is weird that he posted on the site in 2004 that he was ill and was having a problem keeping up with phone calls and shipping. No updates since then. I guess I'll try calling and see what's up. Thanks again. Jim

[Sun Tuned]

Try a step up voltage regulator. 18v ought to light em up a touch. Just be sure to have some extras on hand as they don't burn as long as original at that voltage level.