10.5:1 is way too high anyway.... stay low and run cheap gas! In all seriousness i was honestly curious at what CR can you get away with **** 87 octane?
I’d keep it below 10:1. Not because that’s all 87 octane will take but because low and mid grade pump fuels are allowed many more fillers and other junk I can’t think of now that premium fuel can’t have.
If anyone wants to know how you can run 12:1 on pump premium they need to study the testing methods for octane rating.
Once that is learned it’s easy to see why needing all that octane isn’t always needed.
The tests have limits or better yet the testing is limited in scope because if it wasn’t it would be difficult to actually determine what the octane rating even means.
We just need to know what the test parameters are and what the limits of the testing shows.