Rotor buttons made of different metal - whats the difference?

[DrNick]

While putting the head back together on the Supra (2JZGE/ JZA80) on Sunday I realized the distributor rotor button had somehow gotten broken in the process. I wasnt fussed as I had received a spare one in with a batch of parts about a year ago, so i went and grabbed it.

Now only when I put them side by side I realized that the actual metal contact part of the rotor is made of a quite different material. The existing one was a dark ferrous metal, kind of like fridge magnet kind of stuff. My replacement had a shiny brass looking metal contact.

I checked and the part number was indeed different (new one was 19102-70160 which is quite common on lots of cars).

Anyway since it was a sunday i just installed it, and it fits fine and the car runs fine. Now I am very curious what the difference could be between these? Since there are different part numbers there must be some reason for this even though physically they are interchangable.

Gurus?

Here is a pic of the two side by side

[MWP]

Thats a very good question...

Im guessing that the coating on the end of the new brass one is a similar material to the large piece on the end of the old one.
They probably worked out how to coat/bond the material to the brass to save on costs.

As for what the material is, carbon something?

[jonathan yee]

the one on the left looks like a 3S rotor, not sure if that has anything to do with it...?

[Sam_Q]

I will point the finger at some form of cost cutting