Offsets

[ej063090]

It seems like everyone on here is pretty knowledgable about offsets. It seems like everyone has different opinions as well. I would just like to be enlightened with some education on offsets. Things like how big of a difference is a 40mm offset vs a 48mm. If I measure correctly, 8mm is not a big difference, but I also know little about aftermarket wheels. I have played around with offset calculators, but the difference seems so minimal. Even going from a 6.5 wheel to a 7.5 wheel, but everyone seems to protest a large offset?

[XRSized]

8mm is a fairly small difference as it's slightly less than 1 cm if you're staying with the same diameter and width of the wheel. But if you're also going from a 6.5" wide wheel to a 7.5" or an 8" than that 8mm is more of a difference.

[SuperchargedMR2]

Originally Posted by ej063090

It seems like everyone on here is pretty knowledgable about offsets. It seems like everyone has different opinions as well. I would just like to be enlightened with some education on offsets. Things like how big of a difference is a 40mm offset vs a 48mm. If I measure correctly, 8mm is not a big difference, but I also know little about aftermarket wheels. I have played around with offset calculators, but the difference seems so minimal. Even going from a 6.5 wheel to a 7.5 wheel, but everyone seems to protest a large offset?

The stock S alloys sit inside the wheel wells a fair amount. To give you something to look at.

Stock Width 6.5" Offset +39mm
Option 1 7.0" Offset +40mm This will stick out +5mm
Option 2 7.5" Offset +40mm +12mm
Option 3 7.5" Offset +35mm +17mm
Option 4 8.0" Offset +35mm +23mm

As the wheel width increases & offset decreases the wheel will fill out the wheel well more & look better. You may have seen this picture before but this is what a 7.5" wheel with a +35mm offset will look like. That 17mm makes a huge difference. These are my winter wheels, my summer wheels are 8" wide with a +35mm offset.

[ej063090]

So if the offset is greater and the wheel width is greater than the wheel will stick put more and more I'm presuming? I am just tryin to be as educated as I can before I invest big money on wheels. I know the rota wheels I'm lookin at are 7.5 with a 48mm offset, will that stick out way too far? Like torres' green wheels far?

[SuperchargedMR2]

Originally Posted by ej063090

So if the offset is greater and the wheel width is greater than the wheel will stick put more and more I'm presuming? I am just tryin to be as educated as I can before I invest big money on wheels. I know the rota wheels I'm lookin at are 7.5 with a 48mm offset, will that stick out way too far? Like torres' green wheels far?

No they won't stick out at all. As the offset gets closer to zero the wheel will stick out more, the bigger the # the more sucked in it will be. A 7.5" wheel with a +48mm offset will be sucked in like the stock wheel. Those green wheels are somewhere near +20mm offset I would guess depending on their width.

[ej063090]

Thank you for the education

[searle]

So, just to clarify, larger offset moves wheel+tire inwards (until tire eventually rubs on inside of wheel well and/or wheel rubs on brakes). smaller offset moves tire outwards (until tire eventually rubs on outer finder lip or sticks out, depending on springs and ride height etc). PS: I used to have a full race prepared 96-SS Camaro, and the STOCK rims (with STOCK SIZED race tires) would rub (under extreme race cornering) on the inside wheel well and our standard "fix "was to take a hammer and hammer in that particular section of the wheel well.

Wider wheel (rim) does not directly change anything, but if you have wider wheel you typically also put on wider tire, hence both inside and outside edge of tire are then both further inside and outside. Get a wide enough tire and you could rub both inside and outside, especially under cornering load (street "posers"sitting in "shine-and-shows" dont matter).

Of course, the effects are cummulative. If you change the offset, and you also change the wheel(tire) width, you get a combined change.

There are also effects on steering geometry and tire wear pattern, load on bearings, etc, but these are usually secondary considerations (except in very extreme cases, and/or if you drive the car in serious perfomance cornering situations).

[SuperchargedMR2]

Originally Posted by searle

So, just to clarify, larger offset moves wheel+tire inwards (until tire eventually rubs on inside of wheel well and/or wheel rubs on brakes). smaller offset moves tire outwards (until tire eventually rubs on outer finder lip or sticks out, depending on springs and ride height etc).

Correct! The larger the offset # the more the wheel move inward. The 10th Gen Corolla has a ton of room though for a very large variation of offsets without rubbing at all, even with lowering springs.