CVT transmission + Sunburst + V12 with an insane amount of boost = this. It can also go at least 200 MPH... in reverse!
It hasn't been done because of the mechanical limitations. There is no CVT on the market yet that has the capabilities to handle that much torque. Maybe they could, someone could try and implement it into Beam.
I thought you guys were talking about the game Big Rigs: Over the Road Racing and not “big rig semis” as the vehicle type.
Personally, I like CVTs for the smooth acceleration they allow for due to eliminating the wait for gear changes. My 2014 Honda Civic has a CVT, and its nice and smooth.
The reason they aren't mainstream is because the majority disagrees with you; they love the gearshifts. A car doesn't "feel right" without an automatic, some say. Don't quote me on this, I may or may not be remembering this right.