Relays

[Cs19]

You are correct, except they only use one activation wire (and ground) to trigger both sides of the "poles".
How many prongs are there for juice to go out to your accessories? 4 right?

[Oldsquirt]

MSd has their head up their ass.
On their diagram page they call it a DPDT relay.
Maybe someone can tell by looking at the wiring diagram.
http://www.msdignition.com/pdf/8961_...rm%2024380.pdf
Thanks for your help..
CS
Chris, by the diagrams shown on MSD site, the 8961 is SPDT, the 8960 is definitely a DPDT.
Why does msd claim the large relay is good for activating multiple accessories at one time?
Because it has two separate switch circuits both activated by the same trigger. Current carrying capacity of each switch circuit is higher than if you did the same thing with a SPDT or SPST relay, and wiring is also slightly simpler than using a pair of relays.

[Oldsquirt]

How many prongs are there for juice to go out to your accessories? 4 right?
If you are referring to the 8960(the bigger one), there are only two output circuits if you are simply using it to turn loads either on or off. Look at the pic. There are 8 terminals. The 2 at the one end are the "control" circuit terminals. At the other end there are 2 rows of three terminal. Each row of three are one output circuit and are electrically separate from the other. With relay "OFF" the center and inner terminals are connected(closed). When you activate the relay("ON"), those terminals disconnect(open) and the center and outboard terminals "close".

[Cs19]

Thanks oldsquirt now im tottally consfused.

[Oldsquirt]

Sorry. Would it confuse you more if I mentioned that the 8960 can be used as a DPST as well, and even in 2 different modes(on-> off or off-> on)? I work with this stuff daily as the auto manufacturer whose products I deal with seems to think there's nothing better than more relays under the hood and dash.

[DEL51]

No shit! And i did this shit in the military. Keep it simple as possible. Do not read too much into high end bullshit. Find out how much current draw is from your solenoids and give this number some room. If you are running an alternator your voltage will give you some leeway.All wires are not the same. find wires that are high end, more strands per gauge. Check out some of the car audio shops.Some carry real nice components. Grounds, cant have enough of them. Vibration, secure the relays and solenoids as well as possible. Noise, you can induce spikes into wires for your data recorder. mounting is a consideration. Maybe a nice capacitor can help this. I am sure you heard this crap before but I am re stating this in case you may have left something out. I used the bosch relay, S.P.S.T. for a full time fuel pump.BG400@18psi regulated down for 7psi.The relay never failed in the 60 hrs that i used it. it was a N.O. switch.

[stix818]

CS19, I'm sure you have a handle on the matter but for $hits and giggles we use crydom solid state relays for devices that need them, fuel, cooling system and NOS when I made the mistake runnig that $hit!!!! They take vibration extremely well!!!!!!

[Cs19]

CS19, I'm sure you have a handle on the matter but for $hits and giggles we use crydom solid state relays for devices that need them, fuel, cooling system and NOS when I made the mistake runnig that $hit!!!! They take vibration extremely well!!!!!!
Thanks stix, you guys been racing this year? Hopefully see you guys at world finals.
NOS is good stuff, whatchutalkin bout?

[stix818]

We haven't been out yet this year. We plan on making the world finals. Decided to step-up the engine department and attempt to run PCE next year!!! How about you guys??