For reasons I cannot explain the Dynhud only works when set to "Cleanhud" on Iowa. I have spent a long time trying to figure it out to no avail. All other dynhud presets seems to work on all other tracks so far.
I have a few solutions for you.
A] Use the cleanud preset for the Iowa race.
B] Edit the cleanhud however you wish using the dynhud editor.
C] Use this preset I have edited/created from the cleanhud:
Dann's Iowa Hud
"Winners forget they're in a race, they just love to run"