Don't listen to Dean, you're gonna have a blast!
My friend at IGT did it, and he said he was getting up around 130-140mph at Vegas. That's fast enough for a no-joke adrenaline rush.

I wouldn't trade that away!!
And like it was mentioned, you're going to get a much better understanding about oval track racing. In fact, combine your experience of the Altamont cars with the speeds you're going to see at Vegas, and I think you'll really start to see why oval track racing is so popular. Those guys really are on a knife edge at 200mph diceing it up in rush-hour like traffic!
Also, consider it training, because I'm taking you, Matt and Austin back to Altamont for next October's Spectator Challenge. I think with four of us, we should have a good chance of one of the SECCS folks taking home a podium finish!