I assume you're talking about the '98-00 S70 sedan (since the current S70 is a station wagon and therefore not eligible for classification)?
If you're talking about the '98-00 S70, it's essentially an 850 with slightly rounder sheet metal, IIRC. The 850 (93-97 GLT) is already classified in ITS, but I don't know if there are any currently being raced.
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