Of course, these oil changes & valve adjustments are relative to the life expectancy of the engine. I think (hope) Jims 600 hr est is conservative, my oil ch schedule exceeds OEM specs, I am ballparking the depreciation factor to 900 hrs @ 150 hrs per year = 6 years.
The 4th-century Tomb of the Lionesses consists of a small chamber with gabled roof. The painting depicts flying birds and dolphins and scenes from the life of the Etruscan aristocracy. The 6th-century Tomb of the Hunting Pavilion shows the view seen through the transparent fabric of the pavilion.
Etruscan Civilization, culture created and developed on the Italian Peninsula by the ancient people of Etruria during the 1st millennium BC. At the time of its greatest power, between the 7th and 5th centuries BC, Etruria probably embraced all Italy from the Alps to the Tiber River.