I believe in a lot of the world, going by broadcasts of the JGTC races, its pronounced "Suh-lee-kuh". But to each his own. Here in the south, I say it, and always heard it said, "Sell-ick-uh". Every part of the world has their own pronunciation of car names. Watch WRC broadcasts or Fifth Gear on Speed. Hyundai (Hun-day) becomes "High-un-dye". Jaguar (Jag-wire or Jag-war) becomes "Jag-you-are". Nissan (Nee-sahn) becomes "Niss-uhn". And Z in a car designation is never Z, its Zed. So the Nissan 350Z is the Niss-uhn Three Fifty Zed.