Thanks Chili .. I'm thinking the day program will be fine with the 1.4 (yes, 1 stop) , Texas stadium has the hole in the roof., so usually one side of the track is in sun/daylight. Seems like that's the best time to get shots anyway, I usually end up watching the racing and forget I have a camera with me :p
As far as grainy images at higher iso's the 20D you have Okie is a good performer at higher iso's. Keep in mind these aren't fine art shots but racing shots you're after. Here is a couple of examples of iso1600 shots from an AX earlier this year with lighting much worse than you will have at Dallas. No noise reduction software was run on these either, exif data is still intact if your curious.
*Edit*
I tried to embed them into the post but the img tags are off I guess for this forum, just hit the links to see them.
I'm going to bring my gear to Nocona, but not to the race. I just don't feel like lugging all that around. I'll bring my stuff to Red Bud this year. Hopefully I can get a pass, or a vest...
I shot very little at St. Louis this year. Not sure if it was the disappointment of seeing a buddy of mine shooting from the floor while I was in the stands, or feeling bad about dragging my dad around while I shot. Also this year there was a lot more people there during afternoon practice and quailifers than in years past so it was tougher to move around to the perfect spots.
I'd be hesitant to leave my gear in the car though, I wonder if the facility has any lockers or something?