May sound like a stupid question but im still learning some thihgs here. What/why are realys used for the solenoids? I know what they do and how they work but how critical is it to use um? Reason i ask is because every kit comes with them and i know a hand full of people that dont use um and there system works fine. I got one for my kit, its a 40/30 amp one. For instance my buddy has the NX MAF kit and his noids are pretty big and hes not using any relays, got it wired from the micro switch and it works fine. Fill me in on the tech part of that. thanks

 

They are used to keep your switches from having to handle the full amperage needed by the solenoids. If you don't use them you will destroy the switches. They are only designed to handle a few amps.

 

i don't use any relays and mine worked fine for a year or so but unfortunately right now i have a problem either in the switches or microswitch.

 

Trying to run that much current through a switch will eventually burn the contacts inside the switch. Each time you flip the switch, there's an arc inside that will eat up the copper pads.

 

You can run it with out a relay if the arming switch is capable of handling the amperage. NOS started using relays on the fuel injection kits as a c.y.a. thing they didn't want to potentially be on the hook for frying someone’s computer. But the plate kits still came with just an arming switch.

 

Ya mines hooked up to an arming switch and then all ive gotta do is get my button out and well thats it so no relays or whatever for me.

 

i just bought a relay for my kit, cost me $24 bucks....we use the relay from some recalls for cavaliers...they work just fine

 

i got my relay for $15, so 15 more min. of wiring and i know ill have all the power i need to run um. But just wondering.

 

A couple reasons why relays are a good idea. Yes, some of the small low amp draw noids work fine with out a relay. However, even then, if you have a problem do you want the high amp wire in your interior? Have you guys ever had a melt down from a high amp wire in the interior, not good, a safety reason to have high amp wires in the engine bay only.

Another reason, especially on higher amp noids, is to have the battery 12v source as close to noids as possible. You have have less current draw through having less resistance by keeping main power wire short, and noids will work better and last longer this way.

I wire all my devices this way. The low amp side of the relay only requires a few milla amps to activate the high amp side. So, all your low amp switched 12v sourced relays can be supplied by one keyed 12v source in the interior and they all won't add up to one amp, very, very safe and efficiant to do it this way.
Robert

 

what kind of relay is this? standard bosch ones are like $4 and that's a lot to me for a relay.

here's a $5 one. http://cgi.ebay.com/RELAY-and-with-S...QQcmdZViewItem

 

not sure, but my local speed shop sells some for $15, and there a WELL known shop for what they do. So ill spend the extra $10 KNOWING they work!

 

think most kits use a 30 mp relay...useually a few bucks at most..relays a relay to me, i think most of the ones that are a small black square are a 30 amp...