i typically change my oil every 5k miles, or 16 -20 sessions. With the oil burn from the PCV I'm topping off every 2-4 sessions typically. I work from home, so I rarely drive anywhere, and thus I see no need to change oil between events. After 5k miles or 16 sessions, my oil is very dark and has that very noticeable used oil smell. Blackstone results show this oil to have some mild contaminants but indicate an otherwise excellent health. Typically for fall/winter I run the 5-40 or 0-40 and during the warmer months i run 10-60.
When the weather is in the 40s is when the rough idle starts to be noticeable until warm, but it's really very noticeable in the 20s. Once warm, it all seems to operate okay, but surprisingly the heavier oil doesn't seem to take long to warm up. I wonder if that's because denser oil has greater friction?
I notice you're in Denver; do you frequent High Plains? I plan to make it out to at least one event at High Plains in 2020. You should consider a drive to Topeka, KS for Heartland Park
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