Wheel fitment. Help

Hooligan

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Hey guys,

So I just lowered the car with the cj pony parts springs. Lowers front by 1.5 and rear by 1.0
Now for Christmas I got a set of SVE wheels that are 20s instead of my factory 19s. What size tires do I need to run? Or is the car to low now for 20s? Do I need spacers?

Im attaching picture of wheel specs

AC616592-17C5-4F99-902E-00052B2C74FF.jpeg


BC9B8AE3-FBEE-493E-8EE3-DA9689D25EFE.jpeg


E6245C46-DE7D-46BE-9BFD-0C291D24F89D.jpeg

 

Juantrickpony

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Too low? That’s subjective on here. I don’t think so (if you’re not tracking it, which wouldn’t be smart on 20’s anyways).

Take a look at the sizes LMR includes with their packages. They’re usually pretty safe and still a decent ride (profile wise). Looks like 255/35 for the front and either 275/35 or 285/35 rear.

https://lmr.com/products/mustang-sve-xs5-wheels-15-20

Personally I’d get wider wheels but these should still look good. Post pics when you mount em up. Here’s a pic from LMR. :thumbsup:

624CA682-A557-4032-90A7-AC25082B0919.png
 

MidwayJ

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Too low? That’s subjective on here. I don’t think so (if you’re not tracking it, which wouldn’t be smart on 20’s anyways).

Take a look at the sizes LMR includes with their packages. They’re usually pretty safe and still a decent ride (profile wise). Looks like 255/35 for the front and either 275/35 or 285/35 rear.

https://lmr.com/products/mustang-sve-xs5-wheels-15-20

Personally I’d get wider wheels but these should still look good. Post pics when you mount em up. Here’s a pic from LMR. :thumbsup:

624CA682-A557-4032-90A7-AC25082B0919.png
Agree with the previous reply. You also asked about spacers. With those offsets (+20 front, +35 rear) you will not need spacers.
 

fmc_smt

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Might consider spacers , running velgens with following specs , on a sportine drop , so approximately 1.5 in front and rear fronts 255/35 20 wheels 20x9 +35 rears 305/30 20 20x10.5 +45 . No rubs and set flush ..

IMG_20210117_112719_768.jpg


20200614_112820.jpg


20200614_114024.jpg
 

MidwayJ

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Might consider spacers , running velgens with following specs , on a sportine drop , so approximately 1.5 in front and rear fronts 255/35 20 wheels 20x9 +35 rears 305/30 20 20x10.5 +45 . No rubs and set flush ..
Why would he consider spacers? With +20 offset his front wheels will sit 15mm further out than yours, and his +35 offset rear wheels will sit about 4mm further out than yours (taking into account your wider wheels).
 


fmc_smt

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Why would he consider spacers? With +20 offset his front wheels will sit 15mm further out than yours, and his +35 offset rear wheels will sit about 4mm further out than yours (taking into account your wider wheels).
Your right ..... the offsets always screw with my math in my head .
 

TopJimmyCooks

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Hey guys,

So I just lowered the car with the cj pony parts springs. Lowers front by 1.5 and rear by 1.0
Now for Christmas I got a set of SVE wheels that are 20s instead of my factory 19s. What size tires do I need to run? Or is the car to low now for 20s? Do I need spacers?

Im attaching picture of wheel specs

AC616592-17C5-4F99-902E-00052B2C74FF.jpeg


BC9B8AE3-FBEE-493E-8EE3-DA9689D25EFE.jpeg


E6245C46-DE7D-46BE-9BFD-0C291D24F89D.jpeg
I’m sure you are already planning to do this, but lower aspect ratio in order to keep Speedo accuracy. I don’t know what you have on there but this calculator will help you decide between 30 or 35:
https://www.discounttire.com/learn/tire-size-calculator

Also, I’m always posting this next link (people are probably sick of it) but I think it is helpful: https://motoiq.com/how-to-properly-select-and-size-tires-for-performance/
 
OP
OP

Hooligan

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I’m sure you are already planning to do this, but lower aspect ratio in order to keep Speedo accuracy. I don’t know what you have on there but this calculator will help you decide between 30 or 35:
https://www.discounttire.com/learn/tire-size-calculator

Also, I’m always posting this next link (people are probably sick of it) but I think it is helpful: https://motoiq.com/how-to-properly-select-and-size-tires-for-performance/
just out of curiosity. I did the speed calculator you sent. I would need to run 30. But for the fronts they don’t really sell the same tire I’m looking for in a 30. Would it hurt to run a 35 in front and 30 in the back?
 

TopJimmyCooks

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just out of curiosity. I did the speed calculator you sent. I would need to run 30. But for the fronts they don’t really sell the same tire I’m looking for in a 30. Would it hurt to run a 35 in front and 30 in the back?
No, but it might mean that the relationship between the rear and front ride height changes. Best is to use that calculator to see. In my case, I calculated the tire sizes to: 1) keep the speedo close to OEM, and 2) keep the rear tire height difference to the front tire height similar to OEM. I was coming from 255/19/40 and 275/19/40. Going with 275/19/35 and 305/19/35 did the trick. Depending on the height difference you might want to raise/lower the front or rear if you are able. I’m not familiar with what you bought, so I don’t know if you can. But since your front wheels are narrower by a good bit, there should be no issue at all.

Here are a couple photos of before and after lowering about 1”. You can do the math in the calculator to determine the height difference of my tires to help visualize how whichever ones you are shopping for might fill the fenders.

7886CC6F-9A8A-42FD-B03F-3540630C49E5.jpeg


DA08A10D-0743-432A-AC4E-355768C8FA97.jpeg
 

MidwayJ

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just out of curiosity. I did the speed calculator you sent. I would need to run 30. But for the fronts they don’t really sell the same tire I’m looking for in a 30. Would it hurt to run a 35 in front and 30 in the back?
I think you'd be fine with 255/35 front and 275/35 rear, or 285/35 rear. The tire diameters of 255/35/20 and 275/35/20 are very close to those of the stock GT PP1 setup of 255/40/19 and 275/40/19. I don't think it's necessary to go to 30 profiles unless you're using wider tires.
 

Juantrickpony

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just out of curiosity. I did the speed calculator you sent. I would need to run 30. But for the fronts they don’t really sell the same tire I’m looking for in a 30. Would it hurt to run a 35 in front and 30 in the back?
If your Ohio roads are as crappy as my Ohio roads I wouldn’t recommend 30 series.
 

 
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