Here's info I found for the Comp TA on Sheldon Brown's site:
The earliest models of the Centurion line had high-tensile steel frames but by the late 1970s and into the early 1980s Centurion's pricier models, such as the Professional and Semi-Professional (late 1970s), Pro-Tour (late 1970s to early 1980s) and the Turbo and Comp TA models (early 1980s) featured Tange's high-end Champion #1 or #2 tubing, a double-butted, seamless chromium-molybdenum (CrMo) steel alloy.
The difference in weight between Champion #1 and #2 tubing (and the later high-end tubing used for Centurions, simply labeled Tange #1 and Tange #2 by about 1985) was so small (less than 3oz for a 58cm c-c frame, all eight tubes) that it seems a bit silly to debate supposed frame quality differences between these two high-end tubesets. The thing to remember is that the high-end Tange tubesets were high-quality CrMo steel which were on a par with high-end Columbus SL/SP (CrMo) and Reynolds 531 (manganese-molybdenum) tubesets.