Ok a while back my a.i.r pipe that ment to my cat the hanger broke and it rattled so untill i fixed it i cut a piece off my old radiator hose and wedged it in there where the stock y pipe splits to go to the passenger side. Well i forgot to take it out once i fixed it and found it about 10 months later completely intact, no melting, warping, nothing. It withstanded the heat being wedged between the pipes for that long that close to the engine.

So i just did a header install and one of my wires is resting on the primary and cant find a way to get it off unless i get a new wire to run it. Just for the time being do you think gettin some small diameter vacuum hose around the wire will keep it from burning up for now. Im also going to put those heat sleeves on it too but im worried about the one actually touching the header

 

The exhaust pipes under the car are ALOT cooler than primary header pipes. They will melt vacuum hose... I know because its done it to me.

Go get some heat sheild sleeves for your plug wires. Thats specifically what they are designed for. They look something like this... they just slide over the ends of your plug wires.