RAMROD so close

After doing 100 mile ride this weekend, I am still wondering is RAMROD going to tough, am I going to finish this ride in a good time and will I mentally be prepared? I have never simulated or road that type of elevation gain. I suspect even at 15-16mph avg pace I can complete this ride in 9 hour. This is my very first ride that is over 100 miles and at an elevation that I normally do not ride at. We will see as I get closer and closer to July 29th.