http://www.sequerra.com/electronics/data/index.html
Go to the Products section and look for the ref. to spoark plug. It is the "Ilenium" plug.

Sequerra is a noted hi-end audio designer, who created an amazing tuner about 20 years ago. He is a bit whacky though, IMHO.

BTW, I am seeing technical refrences to problems with aftermarket plugs in cars with DIS like ours - something to do with polarity inversion which causes misfires, power reduction, etc.

Also, installers overdoing the antiseize and shorting the plugs.

I personally believe that the OEM recommendations are best, although the technical editor at Nutz and Boltz swears the Bosch Platinum+4 are a great design.

HP gains with plugs are usually the result of plug indexing, which can be done with the heads on the car but is a pain in the butt. Racers routinely do it, but they also can check which plug oreintation gives max power on their dynos.