So I got a good deal on a set of 8 Motorcraft DG511 COP's from a 08 Mustang. They were on the car for 5K miles. I know my 07 5.4 uses the same COP's, but inside the spring that is inside the boot, is a magnet about 1" long. My original springs in my COP's did not have this (I just replaced the springs about 2K miles ago is how I know). Does anyone think this will cause a problem? I doubt it, but thought I would ask.

 

Does it look like these?

 

Those are Granatelli brand. Pretty expensive.

 

No, mine are Motorcraft, my originals did not have a magnet in the spring, these new ones do. Both are DG-511

 

I don't know then. Maybe someone just threw some magnets in the spring, lol. If they're the same demensions and don't have too much resistance, they'd probably work. If not, then boots are cheap enough.

 

Hey Summers, I do believe that those are ferrite beads, and not magnets. Those are there to absorb electromagnetic interference so that there is no radio noise generated from ignition firing. Never seen that incorporated in such a way, before. Pretty damn cool, though.

 

Cool, thanks for all the replies guys! I just installed them and they work PERFECT!! Upon further inspection, the new springs I just put on had the ferrite beads as JByrd825 stated.