compression ratio vs octane

moper said

You can also slow down your mechanical advance so it doesnt come full in until 3000. If it has an issue, it will be at low rpm in high gear when the rpms are down and the load is high. Once it starts, it's hard to get pinging to stop. So the trick is to keep the initial ping from happening. Solve the issue at 2300 and you'll be fine at 2400 and up. (assuming there is a problem... :) )

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My advance comes in now full at about 2500 rpm and thats when I have
my vac advance starting to come in as it puts me at about 55 mph.

I also tend to keep the rpms a little higher in the different gears too so I
guess that helps. I have most of the valve clatter gone now and will hopefully get to the exhaust leaks soon. I could slow the advance back
down but it sure drives a lot better advanced!

I've been scouting out all the stations where premium is actually 93
octane instead of 91 or 92 also, surprising how many are different!