How to wire cutoff switch?

#1

Could someone please help me?
I need to locate and wire my cutoff switch.
What is the best/easiest location for the cutoff switch?
Where should I tap into the batter positive side?
Where should I tap into the alternator?

#2

There is a big wiring multi-connection for the various positive leads on engine side of the firewall just in front of the passenger. Most cut off switches are right next to that, interrupting the big cable that goes from the battery to the multi-connector.

If mine is tapped into the alternator, I’m unaware of it.

#3

there are some threads here and on bimmerforums that go in to some alternatives.
e.g. http://forums.bimmerforums.com/forum/showthread.php?t=1162449&highlight=cutoff
For me, the easiest way is to follow the two wires (large and small) that are connected to the battery positive and interrupt both of them with a multi-terminal switch (i.e. each wire needs it’s own circuit).
cheers,
bruce

#4

http://spece30.com/component/option,com_kunena/Itemid,94/func,view/id,23306/catid,9/limit,10/limitstart,0/

#5

not to threadjack, but do you guys have a preference for brand or style of switch? removeable key or not?

I was looking at the longacre 4 pole switch at mid ohio last weekend (continental motorsport had them for $29). Is this a good option or should I be looking at something else? I really only want to do this once :slight_smile:

#6

The LongAcre switch is fine. For an E30 you need at least two poles (one for the main battery lead and one for the DME power lead.

Whether to use a switch with a removable key or fixed key is mostly a matter of preference. But if you intend to use the switch to routinely switch power off a fixed key is better.