28° @ 5000 RPM retarding to 22.5° @ 10,000 RPM then it's steady though the rest of the RPM range.
Now if you can find any of the "Atom" TCI's, a couple of them will change the curve. One retards 3 more degrees & the other advances 2 more degrees than the stock TCI. They were once "legal" in stock classes but, I'm not so sure nowadays.
Brian #89