This is a 2008 Mazda 3 engine. The instruction manual says it needs premium gas only if it's turbo charged. I'm pretty certain it's not since the spot where the turbocharger would
Mazda MAZDA3 Questions - How to replace main fuse 2008 Mazda 3 - CarGurus
Mazda 3 Factory Positive Battery Terminal Connector 2004 to 2009 for sale online | eBay
Duralast Gold Battery BCI Group Size 24F 750 CCA 24F-DLG