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Discussion Starter #1
Hey guys! Quick question concerning tires. How can I increase the overall circumference of the wheel? I have 225/35R18 and I need to increase the height of the car without resorting to adjusting the suspension.
Do I install 245/35 or go higher with 265/35 to increase circumference? (Ie. car height)
 

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Hey guys! Quick question concerning tires. How can I increase the overall circumference of the wheel? I have 225/35R18 and I need to increase the height of the car without resorting to adjusting the suspension.
Do I install 245/35 or go higher with 265/35 to increase circumference? (Ie. car height)
With 225 tires, each increase of 5% in the aspect ratio will raise the car 11.25mm

225/40R18 -- 11.25mm
225/45R18 -- 22.5mm
225/50R18 -- 33.75mm
225/55R18 -- 45mm
225/60R18 -- 56.25mm
 

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Yeah, I think you're misunderstanding tire sizing. a 265 is a wider tire than a 245, not necessarily taller. The xxx/ numbers are a measurement of the width of the tire. The /xx numbers are a ratio of the height of the tire in relation to width. So a 245/35 is 35% the height of 245mm(so ~85.75mm) and 265/35 is 35% of 265(so ~92.75mm).

You can't go too high by adjusting tire sizing without hitting the spring perch. Although I think you are running coilovers?
 

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Discussion Starter #4
Yeah, I think you're misunderstanding tire sizing. a 265 is a wider tire than a 245, not necessarily taller. The xxx/ numbers are a measurement of the width of the tire. The /xx numbers are a ratio of the height of the tire in relation to width. So a 245/35 is 35% the height of 245mm(so ~85.75mm) and 265/35 is 35% of 265(so ~92.75mm).

You can't go too high by adjusting tire sizing without hitting the spring perch. Although I think you are running coilovers?
I do have coilovers :) so if i were to replace the current 225/35 to a 245/45 R18... How much height will it add to the car? (I'm terrible with math!)

I need to raise the car by an inch or so.. Using the coilovers to raise will just look weird :(
 

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Discussion Starter #5
I do have coilovers :) so if i were to replace the current 225/35 to a 245/45 R18... How much height will it add to the car? (I'm terrible with math!)

I need to raise the car by an inch or so.. Using the coilovers to raise will just look weird :(
I think I figured it out!

Current setup: 225/35 R18 is 78.75mm
Proposed setup: 245/45 R18 is 110.25mm

Therefore a difference of 31.5mm which around 1.26 inches increase in height!

Not sure if I calculated that right :)
 

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I think I figured it out!

Current setup: 225/35 R18 is 78.75mm
Proposed setup: 245/45 R18 is 110.25mm

Therefore a difference of 31.5mm which around 1.26 inches increase in height!

Not sure if I calculated that right :)
Probably won't fit up front.

You are going to need some major fender rolling/pulling to even try.
 

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Discussion Starter #7
Probably won't fit up front.

You are going to need some major fender rolling/pulling to even try.
That won't be an issue since I have the LP Gemballa widebody installed :D
 

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Are you trying to run 245 up front. Just to put this into perspective. I run 18x8 +26 up front with a 225/35/18 and I hit the seam before it bends where you can jack the car up. Almost anything will fit in the rear on a widebody in the rear in the 200+ low profile range. I'm 265/35 and that's conservative.
 

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Discussion Starter #10
Are you trying to run 245 up front. Just to put this into perspective. I run 18x8 +26 up front with a 225/35/18 and I hit the seam before it bends where you can jack the car up. Almost anything will fit in the rear on a widebody in the rear in the 200+ low profile range. I'm 265/35 and that's conservative.
After further calculations I figured out that I'll only need a 245/40 R18 in front to increase an additional 1.6" in height. In order to accommodate the 4" width increase in the front end the seem is hammered in to accomodate larger wheel (upto 19") and the increased offset (mine is a 18x8 and -36 offset!)
 

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I think I figured it out!

Current setup: 225/35 R18 is 78.75mm
Proposed setup: 245/45 R18 is 110.25mm

Therefore a difference of 31.5mm which around 1.26 inches increase in height!

Not sure if I calculated that right :)
The diameter difference is 1.24 however your ride height will increase by .62 (half of 1.24) and the top of your tire will be .62 closer to the fender.
 

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Discussion Starter #12
The diameter difference is 1.24 however your ride height will increase by .62 (half of 1.24) and the top of your tire will be .62 closer to the fender.
Damn ur right.. an increase of 0.62" and not 1.24... Installing the LP Gemballa is a lot more complicated than I would've ever imagined :(
 

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After further calculations I figured out that I'll only need a 245/40 R18 in front to increase an additional 1.6" in height. In order to accommodate the 4" width increase in the front end the seem is hammered in to accomodate larger wheel (upto 19") and the increased offset (mine is a 18x8 and -36 offset!)
Even if the Seam is hammered flat a 245/40 will hit the wall of the wheel well on the rear of the tire when you turn the wheel.
 

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The diameter difference is 1.24 however your ride height will increase by .62 (half of 1.24) and the top of your tire will be .62 closer to the fender.
Tire Racks website states 'The 50 indicates that this tire size's sidewall height (from rim to tread) is 50% of its section width.'

From: http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=46

And this tire size calculator: http://www.powerdog.com/tiresize.cgi
also figures the difference in diameter to be twice the difference in sidewall height.
 

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Discussion Starter #15
Even if the Seam is hammered flat a 245/40 will hit the wall of the wheel well on the rear of the tire when you turn the wheel.
It wasn't an easy task but the seam AND the wall were hammered in about half an inch back.. One of the instructions LP provided when installing the 25-piece body kit.
 

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It wasn't an easy task but the seam AND the wall were hammered in about half an inch back.. One of the instructions LP provided when installing the 25-piece body kit.
Hey Marvin, so what size of tires you ended up getting? I plan to follow your plan as well
 
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