Barros Negros romped to an easy wire-to-wire victory today in the 11th running of the Eustis Cup, his six-length victory over Bel Esprit II in the four-mile, 23-jump steeplechase giving the dark brown gelding a big boost toward the Virginia timber horse of the year award.

It was the second time Dr. Ralph Lynch's 10-year-old son of Banya has won this timber classic. His rider today and in 1973, Louis Paddy Neilson, won his third Eustis Cup to tie Dr. Joseph Rogers as the only three-time winners of the race. Neilson won last year with Flying Boxcar.

Only once during the almost nine minutes the race took was Barros Negros seriously challenged. That came in the long downhill run between the 21st and 22nd fences when Bel Esprit pulled even.

The bid by Ross Pearce was shortlived, however, as Neilson let out his horse and was again in command at the 22nd jump. Barros Negros his lead over the final fence and up the long stretch.

Pearce's second-place finish on Bel Esprit clinched the top rider of Virginia award for the young Monkton, Md., rider. The three points gained in this race plus a point earlier in the long afternoon gave him 32 points and the title. Randy Waterman was second in the final standings with 25, Randy Rouse, the Seventh Corners champion, was third with 23 and Mike duPont was fourth with 21 points.

The ladies' championship was won by Patty Cassel for the second year running. Her victory was clinched at the 13th jump of the Ladies' Timber Race when her closest rival, Diane Dedds, went off Manko Capac II. Cassel, the defending titlest, finished with 20 points, Dedds with 15.

The hotly contested First Colony Life series went down to its final race with High Peak finishing a third behind Colony Bound and Blue Nerco to gain the all-important three points to finish the spring with 20.

Charles Owens' 7-year-old Happy Nasrullah jumper succeeds Kevin Palmers' Kool Kake as the holder of this coveted trophy. "He just doesn't like hard ground," trainer Rob Palmer said after Kool Kake finished out of the money.