August deadline for 2007 merger

The timescale for the proposed merger remains fluid, with some believing it could coincide with Champ Car's new Panoz Chassis, due to made its debut in 2007.

The IRL has not commissioned a new chassis since its current equipment came on stream in 2003 but, significantly, has not yet tendered for its next generation machinery.

"The very worst thing that could happen for the sport is to merge the two series and have it not work," said Kalkhoven. "So if we can get it done in time for next year that would be great. If it takes a little longer that's ok too.

"We know pretty much how we would fit a schedule together but the devil is in the details. So we'll continue to keep our heads down and work for the best interest of the groups and try to get it done the best way possible."

IRL IndyCar Series team owners Michael Andretti, Bobby Rahal and Chip Ganassi were lunch guests of RuSPORT Champ Car chief Carl Russo at Long Beach last weekend, prompting speculation that the reunification of America's top level single-seater championships is closer.

None of them would comment on what was discussed, but they were joined by Kalkhoven.

"Those three men are concerned about the future of the sport, just like we are," Kalkhoven added.