North America's most expensive stallion just got more expensive. William T. Young's Storm Cat, who stood for $300,000 in 2000 at his owner's Overbrook Farm near Lexington, will stand for $400,000 in 2001. The announcement was made after the Storm Cat colt Giant's Causeway won the ESAT Digifone Irish Champion Stakes (Ire-I) for his fifth group I win this year."The rise in the fee reflects a combination of several factors," said Overbrook adviser Ric Waldman. "He has reached another level of progeny success, especially through Giant's Causeway, and is at or near the top on the general and 2-year-olds lists (by 2000 progeny earnings). He also is at the top of the commercial market and gives horsemen the opportunity to hit a home run at the yearling sales."A home run of sorts was hit at the Keeneland September yearling sale, when a Storm Cat colt was sold for a September record of $6.8 million. Storm Cat, a 17-year-old son of Storm Bird out of the Secretariat mare Terlingua, has sired 83 stakes winners, including additional 2000 group I winner Aljabr and grade I winners High Yield, Finder's Fee, and Raging Fever. The last-named captured the Sept. 17 Matron Stakes (gr. I) at Belmont Park.