After a couple hours of searching the web, and a few phone calls later, I was able to locate manufacturers for performance plugs and wires. First the plugs, after talking to a technical advisor from NGK, he came up with a part number for their iridium IX plugs #BKR6EIX, which happens to be one step "colder" than what comes stock (hence the "6" in the part number, stock is "5"). This plug has a copper core with an iridium tip. The electrode even has a "V" shape to help make a stronger spark, and will last just about as long as a platinum plug. The best part is these can be had at just about any Carquest, Pep Boys usally without placing a special order, or you can get them for $9.29 ea at www.racesearch.com . Now the wires, I located a company call Aurora Ignition Wires www.auroraignitionwires.com which sells a set of 8.5 mm performance wires (part #95606 for those without Adobe) for our Xterra's. If you act before Feb 28th, you'll get 10% off the $78.00 American, with FREE shipping to boot!