After watching some dyno #'s from HorsePower TV... I decided to do some research and found this article:

http://www.powerblocktv.com/redirects/dbredirects/redirect.php?id=537

I'm not entirely certain it makes much of a performance difference, but their emissions tests seem to be sound - so at the very least my car is now running cleaner :)

Link to E3 - http://www.e3sparkplugs.com/technology.htm

E3 part number for XLR-V 4.4L - "E3.53"

Videos - http://www.e3sparkplugs.com/mediacenter.php (the 2nd one is the one I saw on TV).

http://i96.photobucket.com/albums/l172/richardyoo/spark%20plugs/IMG_4800Large.jpg

http://i96.photobucket.com/albums/l172/richardyoo/spark%20plugs/IMG_4801Large.jpg

http://i96.photobucket.com/albums/l172/richardyoo/spark%20plugs/IMG_4803Large.jpg

http://i96.photobucket.com/albums/l172/richardyoo/spark%20plugs/IMG_4804Large.jpg

http://i96.photobucket.com/albums/l172/richardyoo/spark%20plugs/IMG_4805Large.jpg

http://i96.photobucket.com/albums/l172/richardyoo/spark%20plugs/IMG_4806Large.jpg

Old plug - after 17k miles:

http://i96.photobucket.com/albums/l172/richardyoo/spark%20plugs/IMG_4807Large.jpg

Since they are new sparkplugs; they will seem to make the XLR-V run like new since they plugs are new. You need to wait to see the actual difference; 500 miles should break in the sparkplugs to see if you are either getting better mileage or/an better performance.

Since they are new sparkplugs; they will seem to make the XLR-V run like new since they plugs are new. You need to wait to see the actual difference; 500 miles should break in the sparkplugs to see if you are either getting better mileage or/an better performance.

Thats probably a very good point.

But in the testing (if you read/watch the links I posted) you'll see that all their testing was done with new plugs.