headlight relays

[SteveJ]

To elaborate on the "extra" pin, that relay has what is known as form C contacts. If you do any research on electrical circuits, you will see the 87a pin referred to as a normally closed contact (closed when there is no power on the coil). The 87 pin is the normally open contact (closed only when there is the power to the coil). The 30 pin is the wiper. The 86 pin is the positive for your coil. The 85 pin is negative for your coil. (Some relays have diodes, and that is why it's important to connect 86 to positive.) If you use a pre-wired base, be sure to remove the wire for the 87a pin from the base. That will prevent you from shorting out anything.

[grantf]

David made parking light upgrade and headlight upgrade harness's for my 77 280 and they work perfect.

Yes I know. I have heard nothing but great reviews for his upgrades. I just would like to do this one myself for the fun of it. But I need to throw business his way, I am thinking of the side marker upgrade, especially because the front turn signals on a 280 are near useless due to there location.

[grantf]

so, thinking about the wiring it looks like I might need to reverse the polarity of the headlight to make this work. Is there anything wrong with this approach a better solution or is this the way to go?

[rcb280z]

Yes I know. I have heard nothing but great reviews for his upgrades. I just would like to do this one myself for the fun of it. But I need to throw business his way, I am thinking of the side marker upgrade, especially because the front turn signals on a 280 are near useless due to there location.

Oh I understand completely. I would have made them myself if I wasn't so afraid of messing with electrical. I'm "chicken" when it comes to that. I love challenges. Just too afraid to try it right now. Keep us posted on the results.

[Zed Head]

so, thinking about the wiring it looks like I might need to reverse the polarity of the headlight to make this work. Is there anything wrong with this approach a better solution or is this the way to go?

I just ran across FastWoman's post from the past about her headlight relay installation. She posted a detailed diagram and reported that it worked great. I think it was in the same thread as her Maxi-Fuse installation. Search her name with Stinger or maxi-fuse or headlight and you should find it, if you want something to look at. I didn't dig in to it so don't know what she ended up with.

The thing with the relays is determining whether you're removing the load from the power supply switch or the high-low beam switch or both. I did a half-way relay and just took the load off of the switch, installing a relay in front of the headlight power at the fuse box. Still running full power through the dimmer switch.

[H4LIGHTS]

Ok I am going to order the amazon ones. The cost is so low what can I really loose?

(hopefully, only) Your headlights at night on an unlit winding road on a moonless night at speed.

Think about at least using a weather resistant relay since I'm sure you are going to locate these outside of the passenger area.

It's amazing what the relay portion internally looks like on a cheap versus a quality known good name brand relay. (Lucas is not included on my quality name brand list)

Make sure you do a professional job, ( correct gauge wire, solid insulated mechanical connections throughout, routing and loom attachments as safely as necessary...)

keep it weather tight and fuse the circuit.

Most of the inquiries I get after the fact are from folks that have done a cheap half-arse'd job and complain about their results, but still want a cheap half-arse'd fix.

[grantf]

(hopefully, only) Your headlights at night on an unlit winding road on a moonless night at speed.

Think about at least using a weather resistant relay since I'm sure you are going to locate these outside of the passenger area.

It's amazing what the relay portion internally looks like on a cheap versus a quality known good name brand relay. (Lucas is not included on my quality name brand list)

Make sure you do a professional job, ( correct gauge wire, solid insulated mechanical connections throughout, routing and loom attachments as safely as necessary...)

keep it weather tight and fuse the circuit.

Most of the inquiries I get after the fact are from folks that have done a cheap half-arse'd job and complain about their results, but still want a cheap half-arse'd fix.

So you are saying that I should use 18 gauge wire throughout and make all of my conections by twisting the wires together and taping them up with masking tape, ok.

Really why would I do a half assed job trying to improve what works already. The reasons I am doing this is to improve the headlight brightness and to take the load off of combination switches that I just replaced. ( I don't whant my new ones burned up). But I know what you mean I have fixed all of the PO's hack jobs and I do not intend on going back to what I started with. So thanks for helping with a relay choice.

Edited February 4, 2012 by grantf

[Powderkeg]

Yes I know. I have heard nothing but great reviews for his upgrades. I just would like to do this one myself for the fun of it. But I need to throw business his way, I am thinking of the side marker upgrade, especially because the front turn signals on a 280 are near useless due to there location.

If you want to throw Dave some business, have him rebuild your headlight/Turn signal switch.

I also had him make a set of relays for my 280Z. They work great!

I think Dave also did a write-up about making your own relays on the zhome.com website.

Good luck with your project!

Dave Ruiz

[Zed Head]

I think that H4LIGHTS just went maybe a little too far in describing why you should spend a little more than $0.25 on a relay for something as important as headlights.You're probably experimenting, like I tend to do, but once you get the relay installed, you'll want to leave it. If you get the wring right, there's no reason to go back, unless you don't like the "click" when you turn on the lights. Spend a few more dollars now and you can do it once and leave it, and move on to other improvements. Read the reviews on Amazon about that relay and you'll see that it's not really sufficient for automotive use, especially if it's in the engine bay.

[beermanpete]

Get the Bosch relays. Parts Express might not have the best price but the relay is good. When I did car stereo and alarm installs oh so many years ago we use only the Bosch relay and never had problems.

[grantf]

Ok so, what relay do you recommend? It seems that even high quality ones are not that expensive. can you show me a relay you recomend? About the rebuilding of combo switches, I have brand new ones (the spares are in a box for safe keeping).

Edited February 4, 2012 by grantf

[beermanpete]

Ok so, What relay do you recomend?

At Parts Express the part number is 330-070. This is a Tyco (formerly Bosch) 30 ampere NO/NC relay. It will work well for the headlights. Use one for each beam (4 in all).