The Mission Bay waters will be churning with fast-moving boats from many classes, but this weekend’s Bayfair races will be headlined by a duel between unlimited hydroplane stars Steve David and Dave Villwock on Mission Bay. These two will head a cast of pilots in 12 jet-powered, rooster-tail spraying machines that will reach 190 mph on the straightaways of the Bill Muncey course. The action will run from 8 a.m. to 5 p.m., beginning tomorrow, Sept. 17 through Sunday, Sept. 19 in the National Air Guard water circus with Degree Men, a deodorant company, as a presenting sponsor. The action-packed show is under the sanction of H1 Hydroplanes and the Bayfair San Diego Thunderboat promotion. For the unlimiteds, it marks their return after last year’s absence for lack of financial support. It marked the second interruption in a series that had continued for more than 46 years. David, a 56-year-old Fort Lauderdale, Fla., real estate businessman, owns a 506 point lead in the battle for the championship after posting three victories this season while at the controls of the Oh Boy! Oberto boat. Villwock won the prestigious Gold Cup in Detroit and owns an overall string of 60 victories. Villwock, the Auburn, Wash., pilot of the Star of Qatar, is only two wins from tying the legendary Muncey’s record 62. He meets the challenge unassumingly, stating: “It’s nice that they are thinking about it.” Some of his big years were in Bernie Little’s Miss Budweiser, a dominant force for more than eight seasons. Both drivers agree that the Mission Bay course is one of the series’ swiftest, but warn that entering the far turn can be difficult, particularly when they’re reaching the highest speeds. “There’s a crosswind coming from underneath the Crown Point bridge,” David said. “It is tricky and it can lift a boat,” said Villwock, a full-time racer. David, who calls himself a weekend warrior, said fans can’t discount the other drivers. “Dave and I may be a hair faster but all we need is a hiccup out there and one of those other guys is going to beat us,” he said. He pointed to J. Michael Riley in the Graham Trucking boat — who has a pair of seconds and a third — and Brian Perkins in the Miss Albert Lee Appliance boat — who finished third in Seattle — as threats. Other capable drivers are Jon Zimmerman in the Miss Peters boat and May and Kip Brown in the Miss Red Dot. Actually, the slower boats get an advantage in the 2A and 2B with inverted starts and are positioned on the inside. “You need five miles per hour more to catch the guy alongside of you,” David said. ‘That means you’ll have to change the gear box, lay back and start your run early for the clock. Jump the gun and you’re penalized a lap.” A cluster of 22 officials on Fiesta Island will be responsible to keep things rolling for the many classifications which include Grand Prix West (GPW), offshore craft, PWC power boats, cracker boxes, tunnel boats and outboards. Several titles will be on the line as teams compete under the American Power Boat Association sanction. The GPW boats, a smaller version of the unlimiteds, are powered by strong-running piston-driven engines capable of reaching speeds of 160 mph. The noise should be reminiscent of the past. For more information see www.sandiegobayfair.org.