CF is not a good material to built RF shielding.
Is not a good conductor, does not have magnetic permeability.

The is 1st line o defense: a shielded spark plug (with resistor), then the rest just mater of use common sense.
It has been spelled in this forum and other similar forums.
Protect your investment in this hobby; I guess this is what everyone is concerned.
I guess this is what matters, obtain the right information, use it the right way, apply it and enjoy.

You don't have to be electrical engineer to understand those facts, search in the web for more information, here is one:

[link=http://en.wikipedia.org/wiki/RF_shielding]RF shielding[/link]

Happy Hollidays to all

Albatross