My first GTX had a somewhat built engine though I never knew the exact specs. Maybe compression was between 10.1-10.5 to 1. It would ping at WOT on 93 octane and have a slight power lag at 1000-1400 rpm. Running a mix of Sunoco race gas to 93 octane boosted it to around 98-100. With that octane it had no pings, much improvement on the hesitation, and even ran a tad cooler.

I tried various octane "boosters" and none did a darn thing regardless of what they claimed. I'd even add the bottles when the tank was getting low to maximize the effect. A waste of $$. It was actually cheaper back then to add 1-2 gallons of race gas than it was to add an octane booster.
At least with the race gas you were getting a set qty of real octane.

RR69s