Offset question

[rahtx]

Apologies if this has been asked a million times, but I've searched but can't seem to find a definitive answer for this.

Basically, I've never changed from OEM wheels on a car before, but I'm looking into possibly changing wheels and tires on my 24 Sport S (non-Max Tow). I'm considering several tire options, but for the purposes of this comparison, I'm using 285/70r17 in my calculations on tiresize.com.

Now I know 285's will fit on the stock 7.5x17 wheels. However, for the sake of this question, let's assume I'm looking at Method 705's (8.5x17 +0). Using the tiresize.com offset calculator tool, it only asks for the new tire size, and I get this:



That's showing nearly a 2.6" poke outside the fenders, which is a little more than I think I want. Is that accurate? Or do I need to account for the change in wheel width somehow since this tool doesn't?

Sorry if this is a dumb question, but I definitely want to do as much research as possible before dropping thousands on new tires and wheels.

Sponsored

 

[ScottBeach]

Soo many online tools. 1 example

https://www.1010tires.com/Tools/Whe...y59uyiPvs58HJfyBQKi3IFriQ73a3CLBGpEaHs3EK8HyU

Strongly recommend staying within 1 inch of stock.

 

[rahtx]

Soo many online tools. 1 example

https://www.1010tires.com/Tools/Whe...y59uyiPvs58HJfyBQKi3IFriQ73a3CLBGpEaHs3EK8HyU

Strongly recommend staying within 1 inch of stock.

Oh, I didn't find that tool, thanks! Maybe my Google-fu was off. So the change in wheel width does change the final offset - I figured it must, but just wasn't positive. Looks like Method 703's come in a +25 size, which would make the poke even less...

When you say stay within an inch, do you mean tire or wheel size, and height or width? I'm researching a ton, and if I can get away with changing tire sizes without changing wheels and needing spacers or something, I don't mind going that route ... as much as I want Method's, I can use those funds for other mods.

I know going too much larger than 33's (or 32.7 in the case of the stock Rubicon size) is going to be hard on gas mileage and performance with the 3.73 gears, so I'm limiting myself to researching using that size for now.

 

[DJK_Juicy]

The online calculators don't know where your fender is. They only know the dimensions of your existing tires and offset vs. your new tires and new offset.

In your screenshot the calculator says you'll be 2.57 inches further out. To know how much poke you'll have relative to your fenders, hold a tape measure up to your existing tires and see how far out 2.57 inches from your existing tires would be and compare that to your fenders.

 

[rahtx]

The online calculators don't know where your fender is. They only know the dimensions of your existing tires and offset vs. your new tires and new offset.

In your screenshot the calculator says you'll be 2.57 inches further out. To know how much poke you'll have relative to your fenders, hold a tape measure up to your existing tires and see how far out 2.57 inches from your existing tires would be and compare that to your fenders.

Good point.

 

[JTdiRtyD]

If you really want to dive down the fitment rabbit hole, check out this tool;

https://www.wheel-size.com/calc/

Go out to the garage, make your measurements, plug them into the tool and get a much better idea of how different combos will fit.

 

[Wheelin98TJ]

Your stock wheels are +44 and 7.5" wide.

Any decrease in offset gets added to the poke.

Any width change, half of that gets added to the poke. Because the offset measurement comes from the centerline of the wheel.

So for example, you go from a +44 , 7.5" wide to a +25, 8.5" wide.

+44 to +25 is a 19mm change or 0.75".

7.5" to 8.5" cut in half is a 0.5" change.

Total increase in poke is 1.25".

 

[ScottBeach]

I mean limit the movement of the center of tire no more than 1 inch wider than stock

As you move center out you are creating a longer levering force on the parts that make up your front end , steering, upper control arm etc.

More load means more likely to encounter a premature failure.

I say an inch others will say more. But it is use case and risk tolerance based

I wheel. So I will put more loads on the parts than someone that is only on roading.

I also don't want to field replace a knuckle or control arm (many wouldn't mind)

It's what you are willing to take as a compromise

Anything over stock will add more loads and higher wear rate.

When I had a Sport it's why I went skinny. My larger tire was a 255/75. A bit wider than stock but over an inch taller. Kept me inside my tolerance window.

On the Mojave i am going to take more risk. But I understand it's more risk by going to a 35 12.5 which will be over and inch in offset change

 

[Janster]

Just from my own experience lately….. It was confusing for me also.

I contacted my local offroad shop…… I live in PA… Poke is illegal here. So, I‘d need to stay ‘legal’

They told me…..I could run 8.5” x 17” wheels with +25 offset (with the 33” stock tires).

This will put the tires about 1/2” out farther than what they are now and still keep them under the fenders/legal.

I haven’t installed them yet… (black Friday sale ). I’m waiting for nicer weather. I want to really enjoy them in the beautiful weather.

You can call your local offroad shop to get their input….. I hope that helps!

Sponsored