WOW! Your CX-30 looks bad ass! I really like what you did and appreciate the risks that you took to go with this setup. I own a Select, which believe or not got me on the high end of my budget, so I won't be switching wheels anytime soon. I do wonder and of course I understand that with 18" wheels, there is less space for "taller" tires. Still, I'm wondering if anyone knows what the reasonable limit is for a taller tire for when the time comes to change tires.
Am I making sense? Basically adding taller tires to the factory 18" wheels. Of course the results will be far from dramatic, but any additional clearance that I can get, plus having the car look a little more aggressive would be nice. I live in Miami, so All Wheel Drive was never an option since it never snows down here. It does rain a lot, but it is nothing that the Mazda can't handle.
Thanks to all of you who so graciously share with us less mechanically inclined your experiences in customizing your CX-30.
Frank G
Thank you for the kind words! As for how much bigger you can go without trouble on 18s, the rim dimensions will play a huge factor. For example, there's a member out there running 235/55r18 BFG Trail Terrains without any reported issues on his stock wheels. However, if you were to factor in a lower or higher offset, that may change. Also, a 235/55r18 in the BFG Trail Terrain will not be identical to the same size by another manufacturer. There are variables to consider.
Just dig and dig for examples to find of people with personal experiences, because anything short of that is guess work and something as simple as offset can get you in trouble.
I made a little handy dandy chart with different possible wheel and tire combinations that would theoretically fit, staying between 215-235 widths. Maybe you can find it helpful. The slight rub at full lock for 235/60/18 is from a CX-30 owner who is running that tire size. This doesn't mean that diameters below 739mm won't rub, it simply means that his do indeed rub on the wheel wells at full lock (the steering wheel turned all the way to one side or the other). I read another user using 235/55/18 and the owner has pictures showing an estimated 1/4" of clearance at full lock. Hope this helps.
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While this can serve as a helpful reference, it's unfortunately not an exact science as there are some considerable variables... For one, the calculated tire sizes aren't always consistent with the sizes the manufacturers put out. Case in point, the 235/60r18 guy who was barely rubbing, runs Falken Wildpeak AT trails, which according to Tire Rack actually measure out to 29.3" in outer diameter, not the calculated 29.09" in your chart. That's a significant difference.
Secondly, wheel offset is a tremendous factor as well. He appears to be running an Enkei TS-10 in 18x8 et40... Our fender liners are so modestly sized, that a few millimeters in or out will make all the difference in the world for clearance.
The best we can do is take calculated risks, or build up a compilation of exact data point combinations that are confirmed to work(not just in tire size but wheel width and offset as well). Once we've accumulated enough data, then we can understand a range of clearances that can be applied to theoretical wheel/tire sets.
I'm now convinced that the taller sidewalls are the key to balancing out the cladding. Filling the gap with bigger tires certainly helps, but I think sidewalls are the biggest thing.
Seeing how close the tolerance is on 16" wheels, I think my rim choices might be too limited, so I'll likely go with 17" wheels.
What I would like to know is how tall of sidewalls I can get on 17" wheels... especially if I go with 225 or even 215. 235/65/17 (29.02") seems like it would likely rub on full lock for the same reason 235/60/18 (29.09") does. But using thinner tires should, I would think, alleviate that too some degree...
...or am I mistaken?
I totally agree! It's crazy how the fatter sidewall effectively pulls the visual focus away from the cladding!
There's a member running 215/60r17 Wildpeak AT Trails on 17x7.5 et40 Liquid Metal Shadows. I don't recall the name, but here's a pic of the car. Their choice of tire was very conservative, as it calculates out to a smaller diameter than stock, but still looked pretty awesome! Visually helps the cladding a ton!
My guess would be that you should be able to go up in aspect ratio by 5%, meaning running a 215/65r17 doesn't appear that it would be problematic for that setup...
For an additional reference point, here are a couple images of how tight my clearance is at full lock, despite being only 27.9" in outer diameter. That 30mm offset has reduced my clearances by pushing the wheel further out by 15mm from stock. It's roughly 1/4" gap at best. I was really tempted to go for 225/70r16 knowing people have cleared well over 29" in OD, but knew that offset and other factors would change the story... It just looked too risky and after seeing the result, I don't think I could have ran the 225s without rubbing:
My gut tells me 215/70/17 won't rub. The thinner width helps at full lock. The downside is, 215/70/17 has a very limited selection of tires in that size. I actually cancelled my Motegi MR131 17x7 order and changed to the Enkei RPF1 17x7. I was a little concerned with the load rating on the Motegis, it was right at the Turbo's limit up front. RPF1 has a higher load rating and is lighter, but more expensive. Since these will be my winter wheels, I considered the Blizzak DM-V2 as they come in 215/70/17. However, at 30 lb each, that's simply too much added unsprung weight. Going with the Crossclimate2, a more versatile all-season, in 215/65/17 is 25.42 lb, coupled with the RPF1 wheel at 14.9 lb, saves 8.48 lb of unsprung weight from the stock 18s. The side wall height difference from 65 to 70 is 0.43". Small deduction in aethestics with the 65, but better retention in handling and braking with less weight.
I did some more data collection with regards to the 235/60/18 dilemma today. The owner says it barely rubs, so I'm digging deeper, as I'd like to run 235/55/19 on my summer setup. More to come on that tomorrow.
Oh wow, that's a bit concerning with the Motegis! I never would have thought to pay attention to the load rating with the idea that it can barely support the weight of a passenger vehicle... I'm currently looking to get Blizzaks with 16" wheels for my wife's CX-5, so I'm back on the wheel/tire hunt. I'd be lying if I said I'm not having fun with it...
I've also been dying to take the CX-30 out in the snow, but I took the whole front end off a week ago to install a 30" curved lightbar and plastidip the grill trim (while it was like 6 degrees out)... So I felt a bit under the weather and have been taking it easy since. Tuned in to see more of what you've got going on with your tire choices.