OSKALOOSA, Iowa -- In the six races so far of the PolyDome Super Series, a World Dirt Racing League touring series, there have been six different winners.

And there will be not one, but two opportunities soon for other drivers to claim feature wins or one of the prior winners to record the first repeat victory.

On Thursday, July 31, the PolyDome Super Series' Super Late Models will invade Bill McCroskey's Southern Iowa Speedway here to compete in the "Dual" on the Dirt for America's Cup, two 30-lap feature races.

It will be the first appearance of Late Models at the speedway in a long time and the first-ever appearance of the PolyDome Super Series, a second-year touring series.

Of course, qualifying heat races, KSE Products consolation races and the Iowa-Illinois Taylor Insulation Pole Dash, featuring the top six drivers in passing points inverted, will start the night's program.

A registration and inspection station for drivers and car will take place from 4 to 6:30 p.m. on July 31. A drivers' meeting is set for 6:30, followed by practice at 7 and racing at 7:30.

Each of the "Dual" in the Dirt feature races will award PolyDome Super Series points and pay $4,000 to win. There will also be a $1,000 bonus to any driver who can win both races and another $1,000 bonus for the driver who is awarded the most points in the two races.

Twenty drivers will qualify for the first 30-lap feature according to their passing point totals from the qualifying heat races. Six more drivers will qualify out of the consolation race(s), and there will be two provisional starting positions based on the current PolyDome Super Series point standings.

The top-20 finishers from the first main event will qualify for the second race, with the lead-lap cars from the finish of the first race inverted for the start of the second race. Any driver who finishes in the top 20 but is not on the lead lap will be lined up behind the lead-lap cars.

A non-qualifiers' race, composed of drivers who did not qualify for the first race and those who did but finished 21st to 28th, will take place in-between the two features. It will determine six more starting positions for the second race. There will also be two provisional starting positions based on current PolyDome Super Series point standings.

The winners of PolyDome Super Series races held so far have been Brian Birkhofer, Kyle Berck, Alan Vaughn, Jimmy Mars, John Anderson and Terry Phillips.

PolyDome Super Series, World Dirt Racing League drivers will compete in these eight races in the month following their appearance in Oskaloosa:

* Monday, August 4 ­ Superior Speedway (Superior, Wis.)

* Tuesday, August 5 ­ Monster Hall Raceway (Unity, Wis.)

* Wednesday, August 6 ­ Red Cedar Speedway (Menomonie, Wis.)

* Thursday, August 7 ­ Freeport Raceway Park (Freeport, Ill.)

* Saturday, August 16 ­ Adrian Speedway (Adrian, Mo.)

* Tuesday, August 19 ­ Echo Valley Speedway (West Union, Iowa)

* Wednesday, August 20 ­ Davenport Speedway (Davenport, Iowa)

* Friday, August 29 ­ Nebraska State Fair Speedway (Lincoln, Neb.)