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So would I be better off going with the +35 offset or even +35 and 5mm spacer? Or are you saying I need to go higher than +45. You'll have to excuse me I'm not well versed on wheel terminology (first set of aftermarket wheels I'll be buying).
Yeah, so to give you a little more info. Offset is calculated by the distance of the mounting pad of the wheel from the center line of the width of the wheel. Positive offsets mean the mounting surface is more outboard from the center line of the wheel, negatives are more inboard.

As you increase the offset of a given wheel, it brings the wheel in closer to the car as long as you're talking about the same width wheel.

Stock G8 wheels are 8" +48et.
Stock CTS-V Gen 2 wheels are 19x9" +51et front and 19x9.5" +56et rear for sedan/wagon wheels. CTS-V Coupe wheels are 19x9" +51et front 19x9.5" +40et rear. Sedan/wagon wheels are perfect fit rear, and fronts need a small spacer to make sure they clear everything on the suspension of the G8.

In general, BMW fitment wheels won't work on a G8; many are around +20et for their offset, so they're too outboard to be good fitment. This is the trap many fall into. We have the same bolt pattern of many European cars, but our offsets are all much higher.
 
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Ok so for the rears, 19x9.5 +45 should be what I go for. And the fronts, 19x8.5 +40 should be what I go or do I need to be more positive than that?
 

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Ok so for the rears, 19x9.5 +45 should be what I go for. And the fronts, 19x8.5 +40 should be what I go or do I need to be more positive than that?
...

As you increase the offset of a given wheel, it brings the wheel in closer to the car as long as you're talking about the same width wheel.

Stock G8 wheels are 8" +48et.
Stock CTS-V Gen 2 wheels are 19x9" +51et front and 19x9.5" +56et rear for sedan/wagon wheels. CTS-V Coupe wheels are 19x9" +51et front 19x9.5" +40et rear. Sedan/wagon wheels are perfect fit rear, and fronts need a small spacer to make sure they clear everything on the suspension of the G8.
 

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Seems everyone has a different idea of what "fitting" and "perfect fit" is.
To me, fitting would be you should be able to remove the springs and have the car on the snubbers before the tire hits anything.
I get the flush look, tire as far out as possible look , but it is not for me, or everyone.
As underlined above, the CTSV, HSV rear was 9.5 - positive 56.
All I can add is the max 9.5 offset with a 285 is 67.
That is what I have and the tires just touch the plastic inner liners at full droop, but there is zero evidence of ever touching in operation.
If you have choices of offset , err to the larger as you can shim out, you can't shim in.
 

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Seems everyone has a different idea of what "fitting" and "perfect fit" is.
To me, fitting would be you should be able to remove the springs and have the car on the snubbers before the tire hits anything.
I get the flush look, tire as far out as possible look , but it is not for me, or everyone.
As underlined above, the CTSV, HSV rear was 9.5 -56.
All I can add is the max 9.5 offset with a 285 is 67.
That is what I have and the tires just touch the plastic inner liners at full droop, but there is zero evidence of ever touching in operation.
If you have choices of offset , err to the larger as you can shim out, you can't shim in.
You mean "+56" right?
 

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My " -" was not ment to be a neg, just a dash between width and offset.
Changed it
 

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Ok. I know this question has been asked 9 million times. I'm about to pull the trigger on new wheels/tires. I've been combing through this thread and others trying to find the info I'm looking for. So here's the plan... I'm wanting to run a 305 in the rear / 275 in the front because well meat... I'm going to have the fenders rolled next weekend. I understand rolling and cutting and the brake line bracket are needed to fit the 305. I'm unsure if the wheels I'm wanting will work with me. So with all that being said here's what I'm wanting to run.

Wheels:
Avant Garde M359
Front 19x9 35mm offset
Rear 19x10 38mm offset

Tires:
Front 275/30/19 or 275/35
Rear 305/30/19

Will this setup work with spacers or do I need to go down in tire size? Car is at stock height but will soon be ordering Coilovers too. (Next purchase) any help will be greatly appreciated.
 

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If you have choices of offset , err to the larger as you can shim out, you can't shim in.
That makes perfect sense. You can always use spacers to push the wheel out if need be.
 

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Wheels: Avant Garde M359 Front 19x9 35mm offset Rear 19x10 38mm offset Tires: Front 275/30/19 or 275/35 Rear 305/30/19 (Next purchase) any help will be greatly appreciated.[/QUOTE said:
I'd make sure the 305 tire is made for a 10" wheel. You might need an 11 or 12" wide wheel for that tire

Sent from my Pixel 4 XL using Tapatalk
 

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I bought AG M610s in the following setup:
Front:
19x8.5
Offset: 40
CB: 69.5

Rear:
19x9.5
Offset: 43
CB: 69.5

No spacers/rings, or any other items needed save some long lugs. I did have to roll my rears but it may have been my tired stock suspension.
 
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I bought AG M610s in the following setup:
Front:
19x8.5
Offset: 40
CB: 69.5

Rear:
19x9.5
Offset: 43
CB: 69.5

No spacers/rings, or any other items needed save some long lugs. I did have to roll my rears but it may have been my tired stock suspension.
Are you using stock brakes? Post pics of your car when you get them on.
 

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I bought AG M610s in the following setup:
Front:
19x8.5
Offset: 40
CB: 69.5

Rear:
19x9.5
Offset: 43
CB: 69.5

No spacers/rings, or any other items needed save some long lugs. I did have to roll my rears but it may have been my tired stock suspension.
So... I pulled the trigger on some custom ESR SR12s
I ordered
20x9 et +35
20x10 et +45

Also ordered some
Nitto NT555 G2
275/30
305/30

Was on the phone with Mike from RevWerks for a few hours. He assured me they would fit with rolled fenders and a little cutting.
Fingers crossed ill post pics when i get them installed. Here's the wheel but mine are black.
180204
 

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I bought AG M610s in the following setup:
Front:
19x8.5
Offset: 40
CB: 69.5

Rear:
19x9.5
Offset: 43
CB: 69.5

No spacers/rings, or any other items needed save some long lugs. I did have to roll my rears but it may have been my tired stock suspension.
What size tires are you using and are you lowered at all? I'm going to go with that very same wheel setup. I too want to know what your brake setup is. I'm doing 4 pot Brembos all the way around this summer so they'll need to clear.
 

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He assured me they would fit with rolled fenders and a little cutting.

Just had to repost that ??
 
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