I am thinking of doing a headlight relay upgrade for my 280z. though I have though about David Irwin's upgrade his is not compatible with a 280z, so I am thinking of doing a hardwired upgrade. So no I am trying to find the best relay to use. Would this work? http://www.amazon.com/Absolute-RLS125-12-VCD-Automotive-Relay/dp/B0002KR9GG

it has 5 pins not four though.

Those are the same relays I have at my shop and plan on using on my 240z.

These are good.

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=330-070&FTR=330-070

I thought about the amazon ones because it seemed to be a good deal with the socket and fuse holder bundled.

That "fifth" pin is to INVERT the relay's operation from turning ON a device to turning it OFF (or turning one device on while turning another off)

This page on the second link providec by Beerman has some additional explanations on other uses as well as a pin explanation of your relay.

http://www.parts-express.com/resources/automotive-relays.cfm

FWIW

E

So 87a would be left out of the circuit?

Correct.

E

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

I'm a fan of wrecking yard relays just because it seems like old BMW is probably better than new aftermarket. My opinion, I could be wrong.

Those are typical Bosch relays and can be found under the hood of any BMW. They're numbered and labeled by amperage. Most come with an internal diode or resistor also to quench the high voltage spike that happens when the switch is turned off. Probably not a problem on a headlight circuit but a little extra insurance.

Just a little more to think about. Plus I like wandering the junk yard, it's like visiting a museum.

That "fifth" pin is to INVERT the relay's operation from turning ON a device to turning it OFF (or turning one device on while turning another off)

E

Just like a threeway switch in you're home, no?

I got a set of five relays plus sockets from ebay for something like $15 shipped.

FWIW,

Leon

EDIT: Here they are: http://www.ebay.com/itm/5-PACK-12V-DC-30A-40A-Relay-Socket-SPDT-Bosch-Style-/390386557009?pt=LH_DefaultDomain_0&vxp=mtr&hash=item5ae4da2051

Edited February 2, 201214 yr by LeonV

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