legacycentral bbs

I want to add some relays to my headlights to boost the output like in this thread
http://bbs.legacycentral.org/viewtopic.php?f=19&t=48824

Could I use some extra stock relays that I have laying around if I go with a 4 relay setup? I'm pretty sure the stock ones only rate up to 20amps. In that other thread and with my other research most ppl say to use a 30amp relay. I've tried to find out any info on these denso 056700-8480 and 056700-9160. I have 4 of the 8480's and only 2 of the 9160's. If I can use these I plan on getting another main fuse box from the bone yard and modding it to hold these relays, I can pick up more relays then if this plan is feasible.

Does anyone know which color terminals do what? Do these have a specified positive and negative?

This pic I found is the only thing that resembles labeling the terminals, is it accurate?



The denso's would have the copper terminals on the left in this pic and the silvers on the right.

Based on the equation, P=IV you should be ok. P=Power (wattage of the bulbs), I=Amperage (what we're solving for), & V=voltage (system voltage 11-14v)

Using this calculator
http://www.sengpielaudio.com/calculator-ohm.htm

You can play with the voltages and bulb wattages to tell you how many amps are being used. Based on the numbers I ran for 55/65 watt bulbs, you should be ok with the 20 amp relays. With this setup you can use one relay for both low beam bulbs and one relay for both high beam bulbs.

As for the relay, the relay should have a diagram on it which indicates what each terminal does. I have the standard relay diagram on my site and it talks about what each does. If you have more questions regarding the relay diagram, let us know.

http://surrealmirage.com/subaru/tip.html#relay

After looking closer at my fuse box I see that the A/C relays all seem to be on a separate bank. I don't know about anyone elses fuse box but mine looks like a 2 or 3 piece deal. It looks like I could take the A/C relay part out and mount it on the side wall. There's even 2 fuse holders on that piece! That'll eliminate the need to have to buy inline fuses.

Thanks for that help Josh. You really are a wealth of knowledge!

You're welcome.

I wouldn't be at all surprised if the A/C section of the fuse/relay box pops out; it would have made sense to design it to be modular so they could just omit that part on base-model Legacies.

I would take a careful look at the construction of the relay and fuse sockets though; the connections may end up being a weak link in your new otherwise heavy-duty circuit. The nice thing about the standard Bosch-type relays is that it's easy to find sockets that connect to them with nice thick wire.