Can someone double check my wheel math?

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Oliver Closehauf

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If my stock wheels are 17x8 with +43mm offset and I'm looking at a wheel that is 18x9 with+12mm offset, I calculate that the inside edge of the rim would move outbound ~3/4 of an inch and the outside edge would move outbound ~1 3/4 of an inch as compared to stock.

Does that sound right?
 
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Oliver Closehauf

Oliver Closehauf

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Thanks! The site doesn't account for increased width, but if I add 1/2 inch to both sides, I do get agreement with my calculations.
 

MADDOG

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It may not be exactly 1/2 & 1/2 as you still need to account for the offset. A 0 offset puts the hub dead center in the wheel width measurement. If it is a positive or negative offset then some change to the numbers needs to me estimated. It's not a huge amount of movement but it's a good thing to know.
 
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Oliver Closehauf

Oliver Closehauf

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Right. I took that into account. The calculator on the site didn't include a width change. It was more for tires than wheels.

It was close enough to what I calculated on paper to call it confirmed.

One wheel site had a "visualizer" where you could pull up your truck, even choose a color and then select the rim to see what it would look like. There is no way its accurate. A 12mm offset would stick out much further than what they show. Too bad too since I really like the pattern.
 

Black1500Ram

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If my stock wheels are 17x8 with +43mm offset and I'm looking at a wheel that is 18x9 with+12mm offset, I calculate that the inside edge of the rim would move outbound ~3/4 of an inch and the outside edge would move outbound ~1 3/4 of an inch as compared to stock.

Does that sound right?
my math confirms yours ... inside edge of wheel will be 18.3mm (~3/4") further outward and outside of wheel will be 43.7mm further outward (~1.75") compared to stock.

check out customoffsets.com's gallery you can put in your wheel specs and they have pics of people with similar stances.
James
 
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Oliver Closehauf

Oliver Closehauf

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Yeah I was there. Thanks :)
Thats what was messing with me. Those pictures were much wider than stock, while the "visualizer" showed a very reasonable factory like stance.

1 and 3/4 inches is just too wide for me. I barley squeeze into my driveway as it is. Unless.....





Nope. I'd have to add flairs. I could probably handle 1 inch further out by going with a more vertical sidewall. The stock tires are kind of donut shaped.
 
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