Same as V4 and V4TT. The V6TT is a regular V6 with a twin turbocharger. V6TTs can either be regular petrol-fueled engines, which power sporty versions of high-grade cars, or hybrid systems used in technologically advanced rally cars.
“With a boosted engine, this car is impossible to beat! Don't tell the cops Unlocked by Breed...Berliner Thunder
“Wait at traffic lights or see if you can be faster than the red light? Unlocked by Build 10...Berliner Bolt