Not legally in the US. Montana had some no-speed limit highways for a while, but their "safe for conditions" rule must have been too hard to enforce. They had posted speed limits last time I was there. The highest speed limit in the US is 80mph in rural parts of Texas. For other states the maximum speed limit varies from 55 to 75 mph.
Oh, and 100 kph is about 65 mph. So if you are thinking in kilos then yes... in most states you can go over 100kph.