Yes, but is 91 at elevation equivalent to 93 for a 93 tune re knock prevention? Would I dare go to a 7% OD damper with stock tune on only 91 even at elevation?
There’s an amazing thread on this on the other forums over at the other Hellcat forums.
It was actually eye opening. Guy with a lot of technical knowledge - and equipment to match - posted all sorts of charts and tables chronicling his drag runs on different fuel. Amazingly, he experienced 4-5 degrees of knock indication on 93 gas (probably with bad DAs, but still surprising). He experienced this consistently until he mixed in race fuel that got him to around 98 octane.
Eventually, the thread expanded on others’ experiences with octane boosters, which a lot of guys use to save money and headache. The boosters all left orange, caky residue over basically everything it touched inside the engine, including valves, bore walls, etc. Someone took the time to do a tear down and post pictures. The residue could not be cleaned off with a rag and needed to essentially be polished or buffed off. It was pretty eye-opening stuff.
If you’re not running a tune, you probably shouldn’t worry about it at all under normal conditions. But everyone who had the data agreed that 98 was a good number to achieve for a day at the track. For $100 or so, I think peace of mind and a clean engine make it worthwhile.