Perhaps due to a trademark conflict with Alfa Romeo, the compact SUV concept that Audi has shown at the 2014 Beijing auto show will likely be marketed as part of the TT line and not get the Q4 badge.
The TT Offroad Concept is expected to come to production in 2016 and may be called the TTQ. Alfa Romeo has previously used Q4, appending it to 4WD versions of the 156 wagon. Alfa also has used Q2 on FWD models of the 156. That may be why the Audi Q1 subcompact crossover didn’t get named Q2 as expected.
Whatever it’s called, the production version of the TT Offroad Concept will be based on MQB modular architecture that is proliferating across the VW Group. It will be about the same size as the compact Q3, but it will have a more sporting character and will be competing against vehicles like the Porsche Macan and BMW X4. Though the concept has an eTron hybrid drivetrain with 408 total horsepower, you can expect the production TTQ to be introduced with more conventional gasoline or diesel powerplants.
So far, Audi has shown coupe and shooting brake versions of the 3rd gen TT and a roadster is expected at the Paris show in October. Putting all of those into production along with a crossover/SUV platform-mate would give Audi something in the TT subbrand similar to what BMW is doing with MINI.