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Oh my f*ck!
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Discussion Starter #1
Ok, I know there has been much discussion about the appropriate wheel size, offset, and hub sizes that the GTO can accomodate.

Here are my questions:

1) Depending on how old the post is, there is confusion as to what the bolt pattern is (5x120 or 5x4.75). I lean towards 5x120 given what I have learned but is there a definitive answer?

2) Is there any reasonable range for offsets that has ever been determined? This can be with or without fender rolling. I am in particular looking at offsets with regard to 18" wheels, x8 in the front and x9 in the back.

3) Is there a place online where one can purchase hub spacers if the wheels you purchase do not include them (such as when you purchase wheels off Ebay)?

4) I have seen posts that say significantly LESS than +48mm offset will require fender rolling, and I have seen posts that say MORE than +48mm offset will require rolling. It can't be both ways from what I know of what offset is.

My purpose is...I'm trying to find out if these wheels will fit or not. I do not know their offset but I will be finding that out tomorrow. I have heard that in most cases BMW wheels will fit so anyways...Thanks. Hopefully the answers to these questions will help more than just me out.
 

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5x120 is definitely correct.

Offsets and wheel sizes were documented well by Howie at Arrowhead.
Search on that and you will get what you need.

Centering rings are available online, I found some after searching for them,
I decided to buy hub centric wheels, so I never saved the names of the
potential suppliers. It will just take some surfing to find them.

It is less clear, as to whether all centering rings will work with all wheels.
I could not get a good answer to that one.

If you can not get centering rings you could still mount the wheels without the
hub centric condition. Many wheel sellers will suggest that. It seems somewhat
shaky to me, but it is your choice.

CarGuy
 

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Resident 10-second Priest
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I believe the BMW wheels are 40mm offset. From my earlier research, OEM BMW rims are the closest to ours, though there are some newer alternatives (like my TSWs). With 18x8's you should fit without rolling. 18x9's in the rear may need rolling. But I'm no expert. My 19x9.5's needed rolling (40mm offset, IIRC).

And definitely go hub-centric. I borrowed a set of non-hub-centric rims and was lucky to make it home with 4 wheels still on the car.

And, umm, you might want to replace the center caps. That or just scratch out the "BMW" and pencil-in "GTO". :) Nice rims, though.

Bottom line: you won't know till putting them on the car, though these are a good bet.

Padre
 

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Oh my f*ck!
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Discussion Starter #4
First, thanks for the information. The OE Creations replica BMW wheels that are carried by Discount/America's Tire are 18x8 and +40mm offset. They however want to charge $410 a wheel, which makes me laugh.

Second, the use of the term hub-centric. Somebody's confused. Getting a hub-centric wheel DOES NOT make your life easy. There are different sizes for the mounting. The GTO is 69 something mm, the BMW 3-series is a 72 something mm. So even though they are "hub-centric", you still need a ring to fill in that 2ish mm of gap.
 

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Howie's post does not list any offsets, other than the stock 48mm, which I have been asking about as well. He said that an 18x8 and 18x9 are the best way to go. He listed ROH drift wheels, but didn't list the offsets.

Howie, if you're out there, please give us the offsets you tried.

I am also interested in if an 18x8 with a 40mm offset will fit without fender rolling, as this offset seems to be about the highest a person can get in alot of wheels.
 

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Hub Centric wheels fit tight to the hub, either with their own center bore or with the correct centering rings.

If you used the BMW wheels with the 72 mm center bore on GTO hubs WITHOUT centering rings, they would be NON hub centric.

Hub Centric wheels use the hub to precisely orient the wheel so that the center of the wheel is on the same centerline as the brake rotor.

If the lug nuts are used to control the position of the wheel they are not hub centric.

This was all new to me also, I had never dealt with this issue before, I guess US car manufacuturers must have made more standard wheels. I have bought a lot of wheels, and had never heard of an issue with the hub.

When I started to look for the GTO and was confronted with this, I found that
some sellers (eg. TireRack) would not sell a wheel that was not hub centric, and others would sell anything with an OK offset, and bolt circle as a "perfect fit" for the GTO.

I have heard some stories about issues with non hub centric mountings, and so I have been waiting until more wheels become available that are hub centric.


Good Luck
CarGuy
 

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CARGUY said:
Hub Centric wheels fit tight to the hub, either with their own center bore or with the correct centering rings.

If you used the BMW wheels with the 72 mm center bore on GTO hubs WITHOUT centering rings, they would be NON hub centric.

Hub Centric wheels use the hub to precisely orient the wheel so that the center of the wheel is on the same centerline as the brake rotor.

If the lug nuts are used to control the position of the wheel they are not hub centric.

This was all new to me also, I had never dealt with this issue before, I guess US car manufacuturers must have made more standard wheels. I have bought a lot of wheels, and had never heard of an issue with the hub.

When I started to look for the GTO and was confronted with this, I found that
some sellers (eg. TireRack) would not sell a wheel that was not hub centric, and others would sell anything with an OK offset, and bolt circle as a "perfect fit" for the GTO.

I have heard some stories about issues with non hub centric mountings, and so I have been waiting until more wheels become available that are hub centric.


Good Luck
CarGuy
Wisely so CarGuy. Can you imagine going 160 MPH on wheels not precisely centered? Stock wheels have been hub centric for a long time, at least on performance and larger cars. Aftermarket manufacturers sometimes skip hub centricity to gain fitment across makes and models sharing a common bolt pattern, but differing hub sizes. This is not a big issue as long as adapter rings are provided for a tight fit. If not, sometimes if the wheel is perfectly round and suffers from no run-out issues, vibration, shake, and shimmy can still result from improper non-centric location. It's also a reason to pay attention to torques specs for the lug nuts on the studs. A drop of oil on the studs to keep them from seizing and galling doesn't hurt either when you either remove the nut, or put one on. :)
 

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Thank you guys... this post looks to actually have all the info in one place. And makes sense. :cool:
 

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Thank God for copy and paste! :)
 

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READYtoROCK said:
Thank God for copy and paste! :)
I Thank God for the ability we now have to share our knowledge, skinned knuckles, and heartbreaks. We were all isolated and unable to forge a composite base of knowledge twenty and less years ago. This new ability can save folks grief and money, and I for one, learn something new every day here! Thanks IT and Related professions, and Thanks DY!... :hail:
 

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flyinlow said:
Howie's post does not list any offsets, other than the stock 48mm, which I have been asking about as well. He said that an 18x8 and 18x9 are the best way to go. He listed ROH drift wheels, but didn't list the offsets.

Howie, if you're out there, please give us the offsets you tried.

I am also interested in if an 18x8 with a 40mm offset will fit without fender rolling, as this offset seems to be about the highest a person can get in alot of wheels.
I have a set of wheels from ROH, the rears are 18x9 51mm 275/35 and Front are 18x8 41mm 245/40, with Nittos, no need to roll. BFG or Dunlop you may need to roll
 

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bclarke said:
I have a set of wheels from ROH, the rears are 18x9 51mm 275/35 and Front are 18x8 41mm 245/40, with Nittos, no need to roll. BFG or Dunlop you may need to roll
Do you have some pics? I'd like to see which wheels you got and how they look on the car. Looking for ideas.
 

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Oh my f*ck!
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Discussion Starter #13
Can anyone confidently say what the MINIMUM offsets are? Is it possible to run, for example, an 18x9 with a 21mm offset on the rear?
 

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flyinlow said:
Do you have some pics? I'd like to see which wheels you got and how they look on the car. Looking for ideas.
I'll try to get some posted tommorow.
ROH Strada (split 5 spoke , 3 piece)
 

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bclarke said:
I have a set of wheels from ROH, the rears are 18x9 51mm 275/35 and Front are 18x8 41mm 245/40, with Nittos, no need to roll. BFG or Dunlop you may need to roll
Could you post a picture of your car, specifically from the rear 3/4 view?
 

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From Howie's info in the FAQ

certainly can’t list all the ones we’ve found to fit – but the answer is not as many as you think. The offset is European. The GTO hub has a 5x120.00mm bolt circle diameter. The offset is 48 mm for both 17-inch and 18-inch wheels. The GTO wheels have 8.0 inch wide rims.

Editor's comment: If you try to recess the wheels further, you'll hit the struts or other chassis parts, especially up front. Have someone turn the wheels, lock to lock, while you look. You'll see what is meant. There is little wiggle room here. If you try to offest them further out, you'll encounter the fender lip at some point, on one side, or both, requiring rolling, or in extremes, worse. There are a lot of wheels offered by vendors now, but I note very few right on the necessary numbers. I'd avoid any that don't fit within the posted FAQ info and specified backspacing.
 

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Black Ice Strada pics, 18x8 front with 245/45/18 & 18x9 with 275/35/18:
 

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Oh my f*ck!
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Discussion Starter #19
Howie said:
Black Ice Strada pics, 18x8 front with 245/45/18 & 18x9 with 275/35/18:
Is that the setup that is mentioned in your all-encompassing wheel fitment thread, Howie? And do you actually carry that setup? And if so, how much?
 

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