Cosworth TC in 1990?

[TeamScandia]

I'm watching the 1990 season and there are cars powered by Chevy A, Judd, Buick, Alfa Romeo, Porsche, Cosworth DFS, Cosworth DFX, and Cosworth TC engines.

I understand the Cosworth DFS was an updated short stroke version of the Cosworth DFX. What was the Cosworth TC?

[Jamski]

I'm going to take a wild guess and say that just refers to "turbocharged", perhaps in the case of someone who compiled stats that didn't know the particular make of a Cozzie.