UPDATE: 02/02/2022, Wheel Project Completed. This thread covers exploring 16" wheel fitment, tire selection and figuring out a custom center cap solution. Please read below for all the details.
RESOURCES:
Wheels: Method MR502 Rally Wheel in 16x7 et30
Tires: Toyo Open Country AT III 215/70R16
Alt Manufacturing Mazda to Method Center Cap Adapters: Mazda CX-30 Method MR502 Center Cap Adapter – Alt. Manufacturing
Original post begins here...
I wanted to swap to all-terrain tires on my 2021 CX-30 Turbo and was determined to run 16" wheels. The limited information out there was a bit discouraging, so I had to find out for myself before giving up on 16s. I wanted to share my personal findings.
I was looking at rally style wheels, then narrowed my research down to the Method MR502 Rally in 16x7 et30. My hopes grew when I learned that they were designed to accommodate STI 4-piston Brembos. Why is that relevant? Using only the finest, lab-calibrated Pittsburgh measuring tape and Christmas Light box, I measured the distance between the center of rear hub to edge of caliper on my CX-30 Turbo and got about 7-3/8". The Brembos, that the Methods are said to clear, actually measure 7-1/2" from center of hub to the edge of caliper (source: Brembo's official drawing). That information as well as the barrel design of the Methods made me feel comfortable enough to order them up.
They fit.... but barely. And I mean, barely. Now the clearance may not be enough for everyone, but Brembo themselves require a 3mm minimum clearance all around, and it looks to be just over that. And without further ado, some pictures with captions.
Unboxing. Ooh La La.

Precision measuring tools in action.

This is gonna be close.

OMG, it's in. I mean, it's on... The hub bore is 67.1mm (a dead on match for the CX-30, naturally hub-centric without the use of rings)

Took out a handy ISO certified we-don't-leave-them-on-the-counter-anymore Home Depot series paint stirring stick for minimum clearance requirements. It's a touch over 1/8", which is over 3mm.

The stick fits... barely. (cast caliper ears)


Continued in next post...