Wheel Offset Variations?

[Jeremy]

Why is one wheel offset of the same diameter/width different than another?

Is it due to design, or lack of available offsets per manufacturer?

[High5er]

So youre telling me that you have two wheels, of the exact same dimensions, and they arent the same? Yeah, you might have some REALLY shitty wheels. I've never had this happen.

You might want to look into concentrating more on how you word your questions rather than the color.

[deevergote]

I'm not sure exactly what you're asking.
Different cars require different offsets for proper fitment. The same wheel design in the same diameter will be made in multiple offsets to fit multiple vehicles.

[af_1132]

I'm a little confused by your questions, but I'm narrowing down what I think you meant to two scenarios:

1. You obtained a set of matching wheels and you measured that the offsets are not the same. Most companies that I have seen design a particular wheel with a particular offset for a particular chassis. Once you designate what car you have, pick your wheel diameter, and pick your width, there is only one offset to go with it. I haven't come across a situation in which a particular wheel with particular diameter and width dimensions has more than one choice for offset for a particular vehicle, but that's just me. Maybe you have, and even though you designated that you wanted a particular offset, they sent you a set with different offsets by mistake. If this is the case, send those wheels back and look elsewhere.

2. You are talking about what you find when you go shopping around for wheels. Different offsets are due to different design goals and fitment needs, as said above. One manufacturer makes a 15x7 wheel with offset +35 while another manufacturer makes a 15x7 wheel with an offset of +27, or even +0. The design goals and/or fitment needs (due to position of knuckle, position of hub, and fender geometry of different models) are different, and the wheels will stick out of the fender (or not) by varying amounts.

There are more measurements involved in wheels than these three, check out this thread: http://www.cb7tuner.com/vbb/showthread.php?t=37130

[Jeremy]

I'm a little confused by your questions, but I'm narrowing down what I think you meant to two scenarios:

2. You are talking about what you find when you go shopping around for wheels. Different offsets are due to different design goals and fitment needs, as said above. One manufacturer makes a 15x7 wheel with offset +35 while another manufacturer makes a 15x7 wheel with an offset of +27, or even +0. The design goals and/or fitment needs (due to position of knuckle, position of hub, and fender geometry of different models) are different, and the wheels will stick out of the fender (or not) by varying amounts.

There are more measurements involved in wheels than these three, check out this thread: http://www.cb7tuner.com/vbb/showthread.php?t=37130

This ^. I was looking on Tire Rack and Kosei k1 17x7 is 42.. OZ Ultraleggera 17x7 is 40.

You might want to look into concentrating more on how you word your questions rather than the color.

Regardless of color, question remains identical. I forget to elaborate sometimes.

[DCB7]

So youre telling me that you have two wheels, of the exact same dimensions, and they arent the same? Yeah, you might have some REALLY shitty wheels. I've never had this happen.

You might want to look into concentrating more on how you word your questions rather than the color.

Regardless of color, question remains identical.

Im no expert but, a wheel with same diameter/width can have different offsets if the face is more sunk in on one than the other. Most manufacturers don't offer different offsets for the same wheels, but they would give the illusion of staggered wheels while keeping the same tire width, which would be cool. Check out the link from af_1132
http://www.cb7tuner.com/vbb/showthread.php?p=3194158

[deevergote]

Many manufacturers offer a variety of offsets in a specific design.
Staggered wheels look cool on RWD vehicles, with wider wheels in the rear for better traction. Staggered fitment on a FWD car looks silly. Either the useless rear wheels are wider, or the front wheels are wider, making it look like a weightlifter that ignores his legs.

Jeremy, what exactly is it that you're trying to learn here? So far, all anyone has told you is what you'd learn by browsing wheel sites (and clearly, you've done that much already.)
So far, all you've done is asked an unclear question, and stated that sometimes you forget to elaborate. So... elaborate!

[DCB7]

making it look like a weightlifter that ignores his legs.

!

lol

These might be different widths,:



or not

[Jeremy]

Many manufacturers offer a variety of offsets in a specific design.
Staggered wheels look cool on RWD vehicles, with wider wheels in the rear for better traction. Staggered fitment on a FWD car looks silly. Either the useless rear wheels are wider, or the front wheels are wider, making it look like a weightlifter that ignores his legs.

Jeremy, what exactly is it that you're trying to learn here? So far, all anyone has told you is what you'd learn by browsing wheel sites (and clearly, you've done that much already.)
So far, all you've done is asked an unclear question, and stated that sometimes you forget to elaborate. So... elaborate!

I didn't realize how much the center design changes the outcome of the final offset.

[deevergote]

The center design doesn't change the offset. The offset is determined by where the wheel meets the hub.

[Jeremy]

The center design doesn't change the offset. The offset is determined by where the wheel meets the hub.

This leads me back to my original question. Which one fits the car better, 40 or 42? Why have a variant? Tire Rack is telling me I could have two different wheels in two different offsets. Wouldn't one be better than the other, or is it the safest offset the other wheel is providing? Basically, which is optimal for clearance?

[steelbluesleepR]

It's literally a 2mm difference, and you will not notice that at all. 2mm is just over 1/16 of an inch, or the thickness of a few business cards.

The offsets are different because they are made by two completely different companies with different designers and different engineers working on different wheels. (I don't think I said "different" enough)

[af_1132]

Staggered wheels look cool on RWD vehicles, with wider wheels in the rear for better traction. Staggered fitment on a FWD car looks silly. Either the useless rear wheels are wider, or the front wheels are wider, making it look like a weightlifter that ignores his legs.

So true. The only reason I can think of having wider wheels in the front are for putting on some wide radials or slicks for the drag strip and some skinny wheels in the rear to reduce weight and drag. Driving around on the road like that...oh my dear...

Jeremy, since those are 17" rims, you need to be careful about tire sizes, or you will have to modify the fenders. Are you at stock ride height? Large sidewalls could present a problem with clearance. Do you have particular tires in mind?

[Jeremy]

So true. The only reason I can think of having wider wheels in the front are for putting on some wide radials or slicks for the drag strip and some skinny wheels in the rear to reduce weight and drag. Driving around on the road like that...oh my dear...

Jeremy, since those are 17" rims, you need to be careful about tire sizes, or you will have to modify the fenders. Are you at stock ride height? Large sidewalls could present a problem with clearance. Do you have particular tires in mind?

The Width for both wheels is seven inches. I'm not asking, "How wide can I go?". Why is there a fluctuation for one given width? Is it due to the center design? Deevergote says no. If that isn't a factor, which is optimal for safer operation, a lower or higher offset?

I'm not trying to start a war, I'm genuinely confused. They have a recommendation of 205/45r17 for both wheels. I understand that they are probably okay for both offsets. I just want to know which is optimally correct? Sorry for splitting hairs.

[deevergote]

Do you understand what offset means, and how it is calculated? I'm not sure you do, and without that understanding, there isn't much we can tell you that is going to make sense.

The CB can fit wheels with offsets ranging from about +38 to +42 with no problem. A little higher and lower can be done, depending on the wheel width and tire size. Some people go for crazy low offsets, such as +0 to +25... and those usually require a bit of negative camber just to clear the fenders (and IMO, they look quite dumb.)

Wheels that have an offset that is too high will hit the brake caliper or the knuckle itself. Wheels with an offset that is too low will risk hitting the fender.