relay with a resistor? please help

[RX7Driver4Life]

Im in the process of puttin all new relays in my fd and i came across this relay that i have attached a picture of. Now this relay from my understanding has a resistor inline with the coil wire. I lost my headlight relay so i cant confirm this. Can anyone tell me if im right and i cant use a regular relay here i would have go add a resistor inline with the coil wire.

And if any one out there still has a stock headlight relay could you please measure the resistance between the coil wires for me so i can buy a proper resistor and put it inline. Thanks everyone.

[halfspec]

What you're seeing is what's called a snubber resistor:

http://www.sourceresearch.com/newsletter/Automotive-Relays-and-How-They-Works.cfm?emART

When the voltage is removed from the coil the magnetic field across it collapses forming a voltage spike. The resistor simply serves as a path to 'bleed off' the spike and protect the control circuit.

The ohm value isn't important. As long as it's an automotive relay with a built in snubber relay or diode, it'll be fine.

Lane

[RX7Driver4Life]

I ordered this
http://pages.ebay.com/motors/link/?nav=item.view&id=380709046621

[halfspec]

I ordered this
http://pages.ebay.com/motors/link/?nav=item.view&id=380709046621

That should be fine as long as you know you need to get a new socket to fit that relay since oem mazda relays don't use the standard automotive relay pin layout/size.

Lane

[RX7Driver4Life]

Yes this i know i have since replace all the relays including tns, retract, headlight(just bought for an iso type plug), fuel pump, horn, foglights(when i install) added a relay for starter wire to take the high amperage out of the ignition switch, and one for engine harness power(injectors, maf, O2s, ignition coils) and gave each circuit an inline fuse since i had all thoes circuits tied to 1 line and directly to ignition switch unfused. Im doing alot of corrections to make the car safer. I had been driving the car on an emergency wiring job for almost 2 years lol.

[halfspec]

Yes this i know i have since replace all the relays including tns, retract, headlight(just bought for an iso type plug), fuel pump, horn, foglights(when i install) added a relay for starter wire to take the high amperage out of the ignition switch, and one for engine harness power(injectors, maf, O2s, ignition coils) and gave each circuit an inline fuse since i had all thoes circuits tied to 1 line and directly to ignition switch unfused. Im doing alot of corrections to make the car safer. I had been driving the car on an emergency wiring job for almost 2 years lol.

Your plans all sounds very good to me. Good job. A good plan is half the battle

The only thing I question a little bit is the starter relay. The ignition switch is made to easily handle the starter solenoid which really isn't a big load / high current draw device. Adding a relay just converts your points of failure from 2 to 3 without any real benefits that I can think of.

Lane

[RX7Driver4Life]

Reason why is im installingba push button start :-D

[radiomike]

Yes this i know i have since replace all the relays including tns, retract, headlight(just bought for an iso type plug), fuel pump, horn, foglights(when i install) added a relay for starter wire to take the high amperage out of the ignition switch, and one for engine harness power(injectors, maf, O2s, ignition coils) and gave each circuit an inline fuse since i had all thoes circuits tied to 1 line and directly to ignition switch unfused. Im doing alot of corrections to make the car safer. I had been driving the car on an emergency wiring job for almost 2 years lol.

Your plans all sounds very good to me. Good job. A good plan is half the battle

The only thing I question a little bit is the starter relay. The ignition switch is made to easily handle the starter solenoid which really isn't a big load / high current draw device. Adding a relay just converts your points of failure from 2 to 3 without any real benefits that I can think of.

Lane

When I used to fit immobilisers in the starter circuit of Euroboxes I would always check the current draw of the solenoid, it was usually between 6-8 amps.  On our Camaro LS3 starter however the solenoid current is much higher, the initial surge would trip our heavy duty 20A bench PSU and I have heard of problems with the starter contacts in the ignition switch on the FDs with V8 conversions.  We have ours wired direct and it works fine but I feel we are giving the ignition switch a hard time.

[halfspec]

Reason why is im installingba push button start :-D

Well there you go. That's definitely the way to go then

When I used to fit immobilisers in the starter circuit of Euroboxes I would always check the current draw of the solenoid, it was usually between 6-8 amps.  On our Camaro LS3 starter however the solenoid current is much higher, the initial surge would trip our heavy duty 20A bench PSU and I have heard of problems with the starter contacts in the ignition switch on the FDs with V8 conversions.  We have ours wired direct and it works fine but I feel we are giving the ignition switch a hard time.

I spend a good bit of time perusing the electronic subforum here and I believe your concerns with the FD ignition switch being paired with a LS starter are the first I've heard of. If it is a problem, it doesn't affect the majority.

Lane

[RX7Driver4Life]

My ignition switch devoloped a divet in it from the current. I had to bend it up a bit for it to make contact again.

[halfspec]

My ignition switch devoloped a divet in it from the current. I had to bend it up a bit for it to make contact again.

i had all thoes circuits tied to 1 line and directly to ignition switch unfused.

I suspect if you've got damage from pulling too much current through the ignition switch, it was because of your emergency setup, not the starter solenoid

My only point is that 20+ Amps through the FD ignition switch in short pulses to engage the starter solenoid is child's play and all the experienced wiring guys here wire their starter circuits to allow it to do just that. A continuous load pulling high continuous current channeled through the ignition switch's start position may be another matter, but that's not what we're really talking about here 

Lane
 

[eyeoutthere]

...
The ohm value isn't important. As long as it's an automotive relay with a built in snubber relay or diode, it'll be fine.

Lane

Should I not assume that all Automotive Relays have a built in snubber?

I have been using these:
http://www.amazon.com/gp/product/B005HFYE1O/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1#productDetails

Should I go back and add my own snubber resistors?

[Speedfab]

Side note:  Some relays use a diode rather than a resistor.  When you have one like that, coil polarity becomes critical.  Just something to keep an eye out for.

[RX7Driver4Life]

Well the emergency setup worked well for about 2 gears lol. The problem was ghat i would have to wiggle the key a bit for it to start so i dissasembled the ignition switch and it had worn down a bit where i believe the starter gets power from i bent it back up a bit and 1.5 years later no issues. I do believe the fd ignition switch can handle it but either way im going push button start so the ign switch can take it easy lol.