There is no single universally fixed “highest Navkar value” sutra in Jain tradition.

The Navkar-worth count is usually a practical counting convention used in certain pratikraman/pūjā paddhatis, and it can vary by tradition, gacchh, and text version.

So:

• Logassa is commonly counted as 4 Navkars
• But the highest-value sutra depends on the specific list being followed
• There is no one sutra accepted everywhere as “worth the most”

If you want, I can give you a common Navkar-value chart of major sutras used in Jain practice.