Some type of Faraday Cage is the easiest and most cost effective way to shield a vehicle/electronic equipment from EMP/EMB weapons,(rubber materials alone, simply will not shield from these, some form of an electrically conductive sheeting or mesh-screen enclosure that is grounded/guarded, must be used).
Another way to aid in shielding from EMB/EMP are to set fuses or breakers in line before the vital equipment inside the acting Faraday Cage/Sheilding. When an EMB/EMP is experienced, the fuse/breaker on the wiring that would act as an EMP/EMB antenna is blown but protects against further conduction of the damaging EMP/EMB waves to the vital equipment.
Then the fuses are all that need to be replaced or breakers reset to resume electronic function(s). This helps to eliminate the manditory grounding of the Faraday Cage/Sheilding systems and allows the Faraday Cage/Sheilded electronics to be moble while still able to function after an EMP/EMB wave attack.

Here are some sites that explain EMP/EMB Weapons/Effects, and Faraday Cages including some mfging tips, along with relating article links...
( http://www.globalsecurity.org/military/library/policy/army/fm/7-92/fm792_11.htm ), EMP/EMB effects.
( http://www.globalsecurity.org/military/systems/munitions/hpm.htm ), EMB/EMP Weapons & effects.
( http://www.unitedstatesaction.com/emp_and_faraday_cages.htm ), Faraday Cages/Sheildings and relating article links.

Theoretical paper on EMP/EMB and 'Directed Energy Weapons' shielding using counter energy domes and globes... interesting read for further EMP/EMB Guard research...
( http://www.cyberspaceorbit.com/teshield.txt ), controversal.
( http://www.borderlands.com/newstuff/research/teslahaa.htm ), more on Tesla and HARRP.
( http://robocat.users.btopenworld.com/updates2.htm ), the U.S. Military in HARRP research... Alaska... Hummm... ?

IMHO, although a smaller, but still effective Tesla-Shield-System sample could be constructed to guard a motor vehicle, the power that would be required is purely a challenge, then there's the point of "Timing the Guard-Shield to an EMP/EMB Weapon Wave" within a moble-shield system... 'sigh'.
I think it would simply be easier to totally coat every micro-inch of your vehicle's electronics with an 'insulating-coating' and then coat again with a metal-ized material/coating along with adding 'attena-insulating-devices' to physically guard against most EMP/EMB Wave Weapons,(or to EMP/EMB-Harden the electronics of your motor vehicle).

Believe as you will.

IHTH

Michael

"Argue for your limitations, and in the end, when all is said and done, they're your's!"

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