Did a quick look at a news article detailing the earthquakes along the San Andreas fault:

“The 1838 earthquake was between magnitude 6.8 and 7.2 and the 1890 quake was between magnitude 6.2 and 6.4, the team estimates. For comparison, the 1989 Loma Prieta quake, also in the Santa Cruz Mountains, was a magnitude 6.9. Each of the 19th-century quakes ruptured a short segment of the San Andreas, some 48 to 62 miles (62 to 100 kilometers) long. The 1906 quake, estimated at magnitudes from 7.7 to 7.9, ruptured the ground for 296 miles (476 km).” According to this article: https://www.livescience.com/43452-san-andreas-fault-historic-earthquakes.html, the last earthquakes that ruptured along the San Andreas fault:

1838

1890

1906

1989

1838 to 1890 is: 52, close to the 51.6 pi cycle

1890-1906 is: 16 years

1906 to 1989 is: 83 years, almost an 8.6 pi

1989 to 2032 is: 43 years, an exact pi.