I have done plenty of research, enough to know what is needed for an s2k but I still don't really understand the big picture. So its basically how close the face of the wheels sit to the hub, but is that it? Is there any performance aspect to it? (ie does lower offset numbers help with handling or anything) I always hear people refer to lower offsets as being more aggressive, but i wonder if there is really anything aggressive about it aside from cosmetic stand point. Also for cars that can do lower offset numbers mean there fenders are more flared? For example most people do +35 for Evo's, why can they do this? Would they gain more clearance if they run a higher offset?



Per Sticky if someone wants more background on offset:
2. What is this offset business?

The offset is the distance from the wheel centerline (midway between the front and back of the wheel) to the mounting face of the wheel that contacts the hub of the vehicle. The S2000 requires high positive offsets. A positive offsets indicates that the mounting surface of the wheel is closer to the front of the wheel than the back. This offset is expressed in millimeters, and is seen as numbers such as "+40" or "et40."

Since the offset is measured from the wheel centerline, and not the outside edge, the required wheel offset depends on the width of the wheel and tire.

 

Offset shouldn't be a juxtaposition between the face of the wheel and mounting hub, although technically, that's what the numbers indicate.

Offset should rather be used as a measure of where the edge of the wheel will sit, in respect to your fender, for "clearance."

As for being "aggressive" that means the wheels are "sticking out" more towards your fending line/edge, making the wheels look more.. "aggressive"

When you see wheels with too high of an offset, then they look too far in, "sunken" as the kids like to call it.

When other cars can run lower offsets, it's because, yes their fenders are wider than yours. If you take a look at the 350Z/EVO/Skyline/ETC without the wheel on, you'll notice that your whole arm can fit in there where as you can barely put half your leg into the wheel well of your S.

You are correct in that the offset does not account for everything when it comes to your fender/clearance/etc. Offset is one part of the equation, with width, tire size, and camber being the other factors. You can also fudge the numbers by rolling your fender lining/tab or having your fenders pulled.

 

That stuff still confuses me.

 

not 100% true. Its also because the S2K hub sits farther out than a WRX or 240 or whatever. A camaro SS has some MEAN stock tires..285mm wide, but it has to have a large offset as well.

 

Well the car you're talking about has the suspension sitting inwards farther from the hub. If you look at the cars I listed, they all have very similar suspension setups.

The best thing to do, for each and every car, is to test fit wheels/tires yourself and see what you like the best. Reading online should only be a guideline as to what you can/can't do.

 

Agreed. As the sticky lied to me! In the rear i have 17X9 with +55 offset and i rubbed. It listed that I can go upwards of 265 but couldnt even fit a 255/40 without rubbing.

 

What's your camber? Hard to believe you're rubbing with 255's on +55 offset. I'm on 245's with +45 offset, my tires should be sticking out another 5mm, and I'm nowhere near rubbing, at ~2.2* camber. Do not fear running 2* camber, my tire wear is even. Keep toe reasonable (to the low end of spec) and tire wear will not be that bad (relatively).

This may or may not help:

Distance from the outer sidewall of the tire to the hub-mounting face will nominally be ~ one-half the tire width minus the wheel offset. (obiviously rim width selection will also affect this to some degree)

Stock front AP2: (215/2)-55 = 52.5mm
Stock rear AP2: (245/2)-65 = 57.5mm
Stock rear CR: (255/2)-65 = 62.5mm

From the stickie, the maximum you can run for this outside-sidewall-to-hub-mounting-face dimension is:
front: 59.5mm (=205/2 - 43 = 245/2 - 63)
rear: 77.5mm (=235/2 - 40 = 285/2 - 65)

Running the equation in reverse you can get theoretical offset required to run a given tire width (assuming rational rim width for that tire width!).

minimum front offset = (tire width/2) - 59.5
minimum rear offset = (tire width/2) - 77.5

If you want to run 245 fronts and 275 rears,
min front offset = (245/2) - 59.5 = +63mm
min rear offset = (275/2) - 77.5 = +60mm

If you only want to run 205 fronts with 225 rears:
min front offset = (205/2) - 59.5 = +43mm
min rear offset = (225/2) - 77.5 = +35mm

Note that you can run very low offsets ONLY if you're willing to sacrifice tire width to the tune of twice the offset-reduction!