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New shoes and tints on the new (to me) 2018 GTR
Verde 20x9 +38mm
Falken ZE960 255/35
A little more "poke" in the front then what I care for but I'll live with it for now
Love them. I’m still looking to move up to the 20 inchers. Would the 8.5 have made any difference or is it the offset?

Plus, how do they feel?


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Love them. I’m still looking to move up to the 20 inchers. Would the 8.5 have made any difference or is it the offset?

Plus, how do they feel?
Thanks! Its a combination of the width and offset. At 8.5 it would have pulled the outside in .25", which I think would have been perfect for my liking. I looked for 20's from 8"-9" with a 40-45mm offset but I couldn't find any in stock that fit the bill, 38mm was as close and I could get. I guess due to covid theres a shortage on rims as well.

For now this setup works but if I ever decided to lower it I would run into an issue with the front and have to run a pretty high neg camber (and/or possibly rolling the fender), not something I really want. Right now I'm trying to figure out how to get just the back .5" lower for a more level look.

The ride? As expected, they are more "harsh". I feel more imperfections and bumps but overall its not bad. I've only had a few riders since the new setup but no one has commented on the harshness. One plus, cornering has significantly improved. I have a few round-abouts and offramps I frequent and I'm able to push it much harder now. I'm pretty impressed. I can only imagine if I got some springs and sway bars under it.
 

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I'm waiting for my gen 3 to arrive but looking at picking up some second hand wheels.
I've found a nice set but offset may be a little low

18x9" with 225x40s 25P offset
18x10" with 245x40s 25P offset

Anyone running something similar?
It's on factory suspension but will put springs in shortly.
 

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How did you get the 225/45 on the 19x9.5 wheels? I’ve had mixed reviews and no one around here would do it.
I was planning on going to the 245/?? For my 19x9.5’s.
Any thoughts??


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How did you get the 225/45 on the 19x9.5 wheels? I’ve had mixed reviews and no one around here would do it.
I was planning on going to the 245/?? For my 19x9.5’s.
Any thoughts??


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Specialty shops will do it, but none of the larger places like Les Schwab for liability reasons; just like how they won't touch a car with wheel spacers. If you can find smaller shops, specifically ones that do stuff with drift cars, they should be able to do at least a mild stretch, which is what mine is. If you're not doing it for a specific reason, such as clearance for a slammed/stanced car, I would probably recommend going with an appropriately wide tire, but 225/45 on a 9.5" is really very minimal. I can get a more head-on photo tomorrow if you're interested.
 

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Specialty shops will do it, but none of the larger places like Les Schwab for liability reasons; just like how they won't touch a car with wheel spacers. If you can find smaller shops, specifically ones that do stuff with drift cars, they should be able to do at least a mild stretch, which is what mine is. If you're not doing it for a specific reason, such as clearance for a slammed/stanced car, I would probably recommend going with an appropriately wide tire, but 225/45 on a 9.5" is really very minimal. I can get a more head-on photo tomorrow if you're interested.
Definitely, I’d appreciate it.


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I see. I guess I was worried about clearance and all. I think someone mentioned going with a 255 or 275 tire. Is that correct?


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Before I get into it, I need to make a correction. It looks like my stock wheels are 7.5", not 8.5". Going from a 7.5" wheel to a 9.5" wheel, without increasing the tire width, means it's getting stretched 1" on each side.

I'll start from the beginning since I'm not sure where your knowledge of tires is. For a 19x9.5 wheel, 19" would be the diameter of the wheel, and 9.5" would be the width. For a 255/45R19 tire, 255 is the width of the tire in mm, 45 is the sidewall height as a percentage of the tire width, and 19" is the size of the wheel it's meant to mount to. As an example, my stock wheels and tires are 17x7.5 and 255/55R17. If you multiply 7.5" by 25.4 you get 190.5mm. Tire widths go up in increments of 10mm, so assuming you wanted practical options, your sizes would be 195, 205, 215, or 225, which is what my car had from the factory. A wider tire provides better grip, so wider is generally better up to a point.

So, with a 9.5" wheel, that would be 241.3mm, so rounding that up to the next tire size would be 245, but of course, you could fit a 255 or maybe wider on there. I wasn't concerned about how much rubber I could fit on my wheels since I don't do any kind of racing or aggressive driving, so maybe you could go wider if that was your goal.

Sidewall height gets into kind of a weird area because what you pick depends on a lot of factors:
  • Are you trying to match the factory tire diameter, keeping stock clearances and speedometer accuracy?
  • Taller sidewalls are more comfortable and transfer less road noise but
  • Shorter sidewalls look cooler
  • Availability of tire sizes, especially given tire type and cost

I'll assume you want to keep the same outer diameter as your stock wheels, so in effect, you're only growing the size of the wheel inside the tire. The outer diameter of the tire is your sidewall height x2, plus your wheel diameter. Below is a chart where I've calculated the sizes of different tires so you can get an idea of what your options might be. Keep in mind that, while the math here is simple, the sizes are still approximations because of where the tires are measured, stretch, and other tire deformations are not taken into account. I'm also rounding to the nearest mm.

225/55R17225/40R19225/45R19245/35R19245/40R19255/35R19255/40R19
Wheel Diameter (mm)432483483483483483483
Sidewall Height (mm)11590101869889102
Tire Diameter (mm)661663685654679661687

So as you can see, if you're trying to match the same outer diameter as the original tire and you want a "properly" sized tire, 255/35R19 would get you there exactly. There are plenty of other options that will get you close, depending on what look and performance you're aiming for. Once you've identified a tire size you think is good, search on TireRack to make sure it's a common size. If you're set on going for a stretched tire, just keep in mind that, because the sidewalls are now at an angle, the diameter of the tires is going to change, so you may want to go up 5% or something to compensate.

If you haven't already purchased your new wheels, you'll also need to take into account the wheel's offset and how much clearance you have between the inside of the wheel and the suspension, as well as the outside of the wheel and the fenders.

Edit: One consideration I forgot to mention is that, with stretched tires, you're also leaving your wheels more exposed and prone to curb rash. Not a huge deal but it's heartbreaking when it happens.

Edit 2: Not Mazda but very relevant
 

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Before I get into it, I need to make a correction. It looks like my stock wheels are 7.5", not 8.5". Going from a 7.5" wheel to a 9.5" wheel, without increasing the tire width, means it's getting stretched 1" on each side.

I'll start from the beginning since I'm not sure where your knowledge of tires is. For a 19x9.5 wheel, 19" would be the diameter of the wheel, and 9.5" would be the width. For a 255/45R19 tire, 255 is the width of the tire in mm, 45 is the sidewall height as a percentage of the tire width, and 19" is the size of the wheel it's meant to mount to. As an example, my stock wheels and tires are 17x7.5 and 255/55R17. If you multiply 7.5" by 25.4 you get 190.5mm. Tire widths go up in increments of 10mm, so assuming you wanted practical options, your sizes would be 195, 205, 215, or 225, which is what my car had from the factory. A wider tire provides better grip, so wider is generally better up to a point.

So, with a 9.5" wheel, that would be 241.3mm, so rounding that up to the next tire size would be 245, but of course, you could fit a 255 or maybe wider on there. I wasn't concerned about how much rubber I could fit on my wheels since I don't do any kind of racing or aggressive driving, so maybe you could go wider if that was your goal.

Sidewall height gets into kind of a weird area because what you pick depends on a lot of factors:
  • Are you trying to match the factory tire diameter, keeping stock clearances and speedometer accuracy?
  • Taller sidewalls are more comfortable and transfer less road noise but
  • Shorter sidewalls look cooler
  • Availability of tire sizes, especially given tire type and cost

I'll assume you want to keep the same outer diameter as your stock wheels, so in effect, you're only growing the size of the wheel inside the tire. The outer diameter of the tire is your sidewall height x2, plus your wheel diameter. Below is a chart where I've calculated the sizes of different tires so you can get an idea of what your options might be. Keep in mind that, while the math here is simple, the sizes are still approximations because of where the tires are measured, stretch, and other tire deformations are not taken into account. I'm also rounding to the nearest mm.

225/55R17225/40R19225/45R19245/35R19245/40R19255/35R19255/40R19
Wheel Diameter (mm)432483483483483483483
Sidewall Height (mm)11590101869889102
Tire Diameter (mm)661663685654679661687

So as you can see, if you're trying to match the same outer diameter as the original tire and you want a "properly" sized tire, 255/35R19 would get you there exactly. There are plenty of other options that will get you close, depending on what look and performance you're aiming for. Once you've identified a tire size you think is good, search on TireRack to make sure it's a common size. If you're set on going for a stretched tire, just keep in mind that, because the sidewalls are now at an angle, the diameter of the tires is going to change, so you may want to go up 5% or something to compensate.

If you haven't already purchased your new wheels, you'll also need to take into account the wheel's offset and how much clearance you have between the inside of the wheel and the suspension, as well as the outside of the wheel and the fenders.

Edit: One consideration I forgot to mention is that, with stretched tires, you're also leaving your wheels more exposed and prone to curb rash. Not a huge deal but it's heartbreaking when it happens.

Edit 2: Not Mazda but very relevant
I appreciate the I depth knowledge. I am lost when it comes to tires so it’s much appreciated. Also notes by my tire screw up in another post. My stock tires and wheels are the 19x7.5 - 225/35/19 I believe maybe the *45 as I don’t have them in front of me and moving to the 19x9.5 rims with a +35 offset. I was worried about clearance as the cars stock and others have said they have had no issues. Maybe put some lowering springs later on but you know, bills. I’m pretty much matching the outer tire size as you mentioned. I’ll definitely take your post into account and probably making it more difficult than it is.


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