John Deere A compression vs octane

I have a 1950 JD A with new pistons at 6.5 to 1 compression. My question is that I put 93 octane gas in it from the pump and I'm getting a small amount of blow by after running it for about an hour. I was wondering if 87 octane gas would make a difference till the rings get fully seated. Is it possible to have to high of an octane gas and cause me problems ?
 
A bit of blow by in a new motor is normal. This will go away as your rings break in and seat. Nothing to do with octane of fuel.
 
At 6.5 to 1 there is no reason to run anything more than 87. If you just put it together hook it to a plow or disk and work it for 2or 3 hrs. That will set the rings and your done .
 
Is enough blow by to push oil out the ventilator pump pipe normal for the first couple of hours? That's what mine is doing right now.
 
Detonation can cause oil consumption by damaging the rings.
The engine would have to be way out of tune with a lean mixture and over advanced timing to knock on 6.5 comp and 87 octane.
 
You might be over doing it a bit on oil pressure. To much oil pressure on a horizontal engine can cause this issue.
 

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