I posted this in another thread, but this mess is NHRA's own making by having a class built on cognitive dissonance: A heads up class with a de facto unofficial index.
I assume one of the goals was GM, Ford, and Dodge would be involved and every year have newer models with improvements ($$$).
At the same time, if the goal is to keep the class at 7.90ish, then why improve something when you can already go at the unofficial index? However, racers gotta race so in a heads up class, racers spend $$$ to run quicker than the other guy.
In essence, it seems NHRA wants the racers to get to the finish line first, but if you go too quick, we'll change the rules to slow you down, making it even more expensive.
One way to keep ET in NHRA's acceptable range is something most won't like:
Maybe NHRA could run altered Top Dragster qualifying rules, except substitute 7.70 or 7.80 for 6.10, and for eliminations run heads up but no quicker than 7.70 or 7.80 or lose (but NO delay boxes). I understand that's not the intent of the class, but if racers are already at max performance NHRA says they want, there's really nowhere left to go.
The 7.50 issue is a legit concern for chassis cert reasons.