"VTEC JUST KICKED IN YO!" is a tongue-in-cheek catch phrase that has evolved into a notorious internet meme. Using African American vernacular, the phrase mocks import street racing culture, or more specifically Honda vehicles or any heavily modified/tuned vehicles by Asian manufacturers.
VTEC refers to Honda’s variable valve timing system which is used to suddenly increase horsepower at higher RPMs. Street racing culture often praised the system for its boost like performance, however, failed to impress other auto enthusiasts.
Here we have the phrase, once again in mocking vein, applied to a snail.
And just in case you were wondering, TMC refers to French television channel Télé Monte Carlo.