what does it tell you in your owners manual?

 

Couldn’t find any mention of which type of gas to use, hence thought of asking the experts here

 

don't have a copy of the US owners manual but have the Canadian one so I presume it should be very similar, and found this on page 3-28 under "Fuel and Emission" (looked up "Fuel" in the index)

 

Mazda lists Regular Unleaded on their website for all CX-30 trims.
So you should be good with Regular 87 octane (US).

2020 Mazda CX-30 - Specs & Features | Mazda USA

 

87 regular unless you are in a really hot environment where engine detonation is prone to happen, then higher grade.

 

Thank you!

 

I'm not a fan of just meeting the bare-minimum engine requirements, so I opted for "top tier rated" SHELL 89/Silver grade octane in my Corolla SE TNG 2.0L direct+port injection engine for the 2.5 years that I owned/drove it. Plus, I only drive about 3300 miles per year these days, so the cost increase is pretty minuscule going from 87 to 89 grade, or even to 91.

 

Fuel grade does make a difference in horsepower and torque, but only on the turbo I believe.

 

I fill up with E-15 88 octane and my '23 seems to run fine on that. It's usually the cheapest choice at the pump.

 

In Australia, I use the recommended 91 Ron, which is your 87. I tried 95 Ron, which might be your 91, it drank it up like water but made no real difference to economy or performance. My car only has the 2.0L in it though, not sure about the 2.5L. If it had a turbo the fuel would make a difference I believe.