Here is what I found and listen to this year..
Ch. 1 462.1250, Ch. 2 462.2250 was the Chili Bowl Officials
454.000 is the Officials to Drivers only.. about 90% of the dirt tracks or series use this frequency to talk to the drivers only..
Never could find the other Frequency the Flagman was talking on.. He had a radio on each ear of his headset
WoO and All Stars Sprint Cars last year was using 451.925, USAC Sprint, Midget & Silver Crown used 464.550 with 454.000 too.