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I installed a very heavy duty headlight harness from NPD. New H4 7" quartz lamps are very bright as I expected.

Problem: Lights work only with RS headlite doors circuit disconnected. When the RS circuit is connected doors open and lights will turn on. Turn HL switch off with ignition on, the lights will not turn off.

With HL sw off and ignition on doors will open and close by pressing floor dimmer.

In short, 1967 RS electric door systems will not work with harness relay because:

Relays R2 and R3 are activated via the blue and brown wires connected to the relay coil circuit (2 wire connector). To close doors positive 12v flows from ign switch to the coils. Current from R2 & 3 coils flows thru the blue wire to ground. However:

The only paths to ground are thru Relay 1 and the wire going from headlite switch to headlite circuit. The current flows thru the lamp filament to ground.

When the upgrade harness is installed the blue wire current seeking ground flows to the "new" harness relays, activating the relays. There lites won't go off with HL switch ......

I removed the upgrade and everything works.
 

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Re: 67 RS headight harness upgrade

I haven't installed my relays yet so no idea if this works - however, a prior thread on this board had this wiring diagram posted with an extra relay added to the RS relay board so as to allow a ground path even with headlight relays installed. I apologize, I don't have the time right now to search through the forums to find the original source who certainly deserves credit...
 

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Re: 67 RS headight harness upgrade

Sounds like the harness to the headlight switch is messed up. Wires not in the right spot in the connection. I used to have some really good files on my computer until they worked on it and lost it. Go on AAW Web site and you might find some info on the RS wiring.
 

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Re: 67 RS headight harness upgrade

Hate to disagree but the problem is that the whole relay circuit for headlight door operation grounds through the filaments of the lights. If you put relays in for the high and low beams, that ground path is interrupted and the headlight doors will not function normally. The above wiring diagram I posted is a bit of genius that another TC member (again, wish I could remember who) came up with to work around the issue; it adds a fourth relay to the RS relay board to supply a ground path in absence of the light filaments being in the circuit. If you invest some time searching the site I suspect you will be able to find some threads on it, but if I recall that diagram is buried deep in an extensive thread, hence my not being able to recall where.
 

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Re: 67 RS headight harness upgrade

I'll be trying it out in the next few months; until then all I can say is that the guy who designed it claims it works, and looking at the schematic the theory seems sound to me.
 

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Re: 67 RS headight harness upgrade

Because adding a headlight relay harness or system to any 67 RS Camaros will then cause issues because the original system of relays cant see the headlight filaments is a common issue folks stumble into in the quest for brighter headlights, I have made this thread a sticky.

The solution of adding a fourth relay to the doors seems to work out for most people and included on this thread is the diagram. I may be mistaken but I thought someone also had a solution by adding a resistor that compensates for the missing headlight filament resistance. If that thread is here I will stick that one too.
 

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Yes. As an update, I've installed the relays with the 4th door relay as above - works great. Reportedly either adding a resistor or an extra headlight bulb (inside the fender or engine compartment, for resistance) does provide a ground path and works. Definitely simpler but I worry about how much heat that will produce. Rewiring the relay board with the extra relay is a bit safer and more elegant, albeit certainly more complicated. Attached is a photo of the bracket I made to hang the headlight relays and fourth door relay as well as some circuit breakers.
 

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Brian - Thanks for the update. Yeah I would be worried that the heat the third headlight especially if pointed towards the fender would do to the paint job. Seems like the relay is the best solution. I wish for the benefit of the community there was a vendor producing this fourth relay set-up so it was plug and play.

Brian - Can you or someone else who has made this modification and took photos of the process post them, especially if the photos show the connections to the factory door board?
 

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Apologies for the delay; having completely rewired my car I wanted to get it started, running, and totally functional before sending anyone off on a wild goose chase with bad directions. I’m afraid I don’t take many pictures while working on the car so I can’t provide those, but I thought a short tutorial might help people add headlight relays to ‘67s with the factory RS setup.

1. Parts: I used Hella weatherproof relays (Waytek # 75605) with Hella weatherproof relay connector/harnesses (Waytek # 75610) as well as a Type 1 circuit breaker (Waytek # 46430). Pretty high-quality parts although there’s nothing inherently special about them and any equivalent relay would be fine. I also hate butt splices whenever they can be avoided so I tried to make fresh connections with Delphi Packard 56-series crimp connectors every time possible. I crimp, solder, and heat-shrink each under-hood connection given the heat, vibration, and moisture. Clearly, there are arguments to be made for not soldering (longterm risk of stress fractures in the conductor with vibration) but I’m a believer in soldering them anyways. To each his own.

2. Power source: My recommendation for this terminal would be to run a power lead directly from the main power distribution point on your vehicle (the horn relay if you have an old externally regulated alternator; I converted to an internally regulated alternator and have a BlueSea busbar on my radiator support but that may be overkill) with a Type 1 (self-resetting) circuit breaker in-line for each circuit (high and low beams).

3. Relay board modification: This is simpler than it looks. Pull your relay board out of your car and identify which relay is #1, 2, and 3 (http://retro-electro.net/FAQ67.html has an explanation on how to identify them and the AAW directions for their RS wiring kit have a picture ID-ing each relay if in doubt). You will note two light blue wires going to one terminal on R1. Disconnect this and cut the connector off so the wires are loose. Then, take the light blue wire coming FROM the firewall (NOT the one going to the other relays) and combine it with the wire from terminal 85 on your new relay; connect them to the same terminal on R1 that you just removed the light blue wires from. You will now have a loose light blue wire leading to R3 and then onwards to R2. Take this loose end and connect it to terminal 30 on your relay (so terminal 30 is electrically continuous with the light blue wire terminals on R2 and R3). Now, connect terminals 87a and 86 on your relay to a good ground. Terminal 87 should be terminated – it does not need to be connected in this. You are now done with your relay board. Functionally, when no voltage is applied to the coil, the light blue wire from R2 and R3 is grounded through terminal 87a. When the light blue wire to R1 is energized, the coil is operated and the new relay disconnects the light blue terminals of R2 and R3 from ground (by connecting them to terminal 87, which is not hooked to anything). This solves the problem with the lack of a ground path through the light filaments after you add relays to the high and low beam circuits.

4. Headlight relays: You will perform the same task twice, once for the high beam circuit and once for the low. Identify the high beam and low beam wires from the firewall to your bulbs and cut them. Pick either highs or lows and take the end of wire coming from the firewall and connect it to terminal 85 on your relay. Connect terminal 86 on your relay to a good ground. This is your coil circuit (and actually, you could swap those terminals if you wanted to). Connect the cut end of the wire going to the bulb to terminal 87 on the relay. Then, connect terminal 30 to your power source. Then, terminate terminal 87a – you don’t use it on this relay. Repeat this sequence for the other (high or low) circuit.

That’s pretty much it. The rest is all just how to mount everything in the limited space available between the radiator, washer tank, etc. This setup worked well for me – with the addition of a set of H4 housings and bulbs from Susquehanna Motorsports, it’s massively brighter than stock. Can’t swear how much is due to the relays as I replaced the whole harness and converted to internally regulated alternator at the same time, but it’s theoretically a better system and definitely cuts back on the amperage running under-dash.
 

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4. Headlight relays: You will perform the same task twice, once for the high beam circuit and once for the low. Identify the high beam and low beam wires from the firewall to your bulbs and cut them. Pick either highs or lows and take the end of wire coming from the firewall and connect it to terminal 85 on your relay. Connect terminal 86 on your relay to a good ground. This is your coil circuit (and actually, you could swap those terminals if you wanted to). Connect the cut end of the wire going to the bulb to terminal 87 on the relay. Then, connect terminal 30 to your power source. Then, terminate terminal 87a – you don’t use it on this relay. Repeat this sequence for the other (high or low) circuit.
Excellent write-up Brian!

Just thought I'd add that terminal 30 should be fused. Inline fuse holder or fusible link wire properly sized to the wire it is protecting.
 

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Thanks! I probably should have been more clear there and very much agree a circuit with that much amperage needs to be protected. Also, as I said in the power source section, I kind of prefer a Type I circuit breaker because it won't risk stranding you on the side of the road with no lights... plus it's what GM used in the first place. However, there's certainly a fair argument for using a slow-blow fuse instead. Not a big fan of fusible links in headlight circuits because they're hard to replace in the middle of the night on the roadside; just personal preference though. I certainly use them elsewhere in the car!
 

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Jonathon- you shouldn't. Judging by your sig, your car is a '68 RS so its headlight doors should be vacuum operated. The above modification is a fix for a quirk of the '67 RS relay board (electrically operated headlight doors) where the addition of headlight relays breaks one of the ground paths for the door operating circuit through the bulbs. The extra relay restores a ground path and normal function, but is only necessary for the '67 RS cars.
 

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Jonathon- you shouldn't. Judging by your sig, your car is a '68 RS so its headlight doors should be vacuum operated. The above modification is a fix for a quirk of the '67 RS relay board (electrically operated headlight doors) where the addition of headlight relays breaks one of the ground paths for the door operating circuit through the bulbs. The extra relay restores a ground path and normal function, but is only necessary for the '67 RS cars.
I'm going back with electric on mine Brian. So it looks like another couple will have to be installed??
 

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Hm. If you've removed a stock '67 RS harness, relay board, motors, and limit switches to install in your '68 then perhaps. If you're using any kind of aftermarket electric conversion kit it's less likely as they probably wouldn't have engineered it this way. Also, the install of the light relays is the same as any car, it's just the addition of a fourth relay to the original three on the relay board for the headlight door operating circuit.

On a side note, I glanced at your build thread - car looks great!
 

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Ok good deal. I will be getting an aftermarket kit not picked one specifically as of yet but yes I will be going that route. I have already installed everything as far as relays and wiring goes out in the engine bay. I'm not too far into it to add anything else so all is good at the moment. I just saw your post and thought it'd be a good time to ask. Thanks for the quick replies.
 

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No problem! I can't swear to it (haven't used an aftermarket electric conversion kit) but electronics have advanced a bit in the past few decades and I can't imagine anyone making a conversion kit with the same shortcoming - the complexity of the '67's electric relay setup just isn't necessary anymore. I think you should be fine as-is.
 

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No problem! I can't swear to it (haven't used an aftermarket electric conversion kit) but electronics have advanced a bit in the past few decades and I can't imagine anyone making a conversion kit with the same shortcoming - the complexity of the '67's electric relay setup just isn't necessary anymore. I think you should be fine as-is.
Thank you again sir!!....:thumbsup:
 
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