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Rims/ Wheel sizing on my ER34 25GT

ArcticsLeftGucci
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ArcticsLeftGucci Apprentice

ArcticsLeftGucci

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Hey,

My wheels I have currently on my car are 17 inches and I was looking at some nice 18 inch rims, I was just wondering if its alright to get 18 inch rims on a 17 inch stock car. (the car has stock suspensions) i know that it can throw off the speedometer but also wondering by how much it would be, is it alot?

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GTSBoy Grand Master

GTSBoy

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On 7/21/2021 at 8:32 AM, ArcticsLeftGucci said:

if its alright to get 18 inch rims on a 17 inch stock car

Of course it is. A 1" diameter increase on the wheel is a normal and trivial thing to do.

On 7/21/2021 at 8:32 AM, ArcticsLeftGucci said:

i know that it can throw off the speedometer

No it won't. The aim when you put bigger wheels on is to choose a tyre width and (lower) profile to keep the rolling diameter of the new wheel/tyre combo to within a few % of the existing rolling diameter. If you have a known speedo error now (say, you can tell it reads 4km/h fast at 100 km/h, checked by GPS speedo or something equally trustworthy) then you can often choose your new tyre sizing to get rid of some or all of that existing error. Not that you would make this your first priority, but it is an available input to your choices.

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