I'm new to forum and tried searching forum for specs on bolt pattern, are there any?

5 x 120 Try searching on wheel bolt or lugs.

Thanks...

I think that it's the standard 12MM x 1.5, or something like that. Just under 1/2" diameter.

I'd still like to know what the weight differences are between the 19's and 18's... I need to have something for the winter so I will probably get the 19's and buy some steel wheels (if they make them) and fit some Blizzacks on them but we'll have to see. I am all for less unsprung weight.

I think that it's the standard 12MM x 1.5, or something like that. Just under 1/2" diameter.

That would be the stud size, not the bolt pattern. The bolt pattern is listed above, 5x120mm. The stud size is actually 14mm x 1.5. The studs are very strong. In 10 years working at a tire shop, I've only seen 1 ever break. And that wasn't even a fault of our shop.

How abou offset? From looking at them the past few days in person, I would say 40-45mm?

Commodore owners have told me the factory offset is +48mm. Just like the GTOs were.

I was scared to guess that high :( That limits our options greatly.

I was scared to guess that high :( That limits our options greatly.

That's not so bad. My Mazda 6 factory wheel has an offset of +60! People are able to mount 7.5 inch wide wheels with +48 offset with no rubbing. But the 6 has a large lip on the rear fender. Roll the lip and you can go down to about +40 with 8-8.5 inch wide wheels. I'm hoping the G8 is aftermarket wheel friendly (although those factory 19s actually look very nice in person!).

I was scared to guess that high :( That limits our options greatly.

Not really. Most GTO owners are running from +40 to +48 with no problem. Give it 2-3 months & people will be testing & coming up with reliable wheel & tire combos.

So if it has the GTO pattern, and GTO studs, why won't a GTO wheel fit then. There should be loads out there at a good price.

Guess what? After some calculating, the 120 MM is like the old Chev standard; 4.75"!

So if it has the GTO pattern, and GTO studs, why won't a GTO wheel fit then. There should be loads out there at a good price.

Olly posted this about 9 months ago:

"We did a Ve to VZ comparison today..here's the results..........
We took a VE alloy rim and tried it on a VZ commodore...the stud pattern is the same but the VE rim won't go over the centre hole without machining. The lugnut holes are larger on VE to accomodate the thicker studs. Offset is for a later post........hope this helps"

Ah, an easy fix. Thank you.

Guess what? After some calculating, the 120 MM is like the old Chev standard; 4.75"!
Ah, an easy fix. Thank you.

Don't let this misconception get the better of you. It's actually: 120mm=4.72" & 4.75"=120.65mm. This doesn't pose a problem to the GTO. I run Trans Am WS6 wheels on my GTO. I wouldn't try that on a G8, though. Why not? The wheel studs on the Ve/G8 are 14mm diameter. GTOs, Corvettes, and Camaros/Firebirds are all 12mm. There is just a small amount of room to not create a problem. But, use a wheel with the 4.75" BP on a G8, & the studs will stick through the holes right at the edges. The studs won't be properly centered in the holes. You won't get the proper tightening with the wheel like that. If it's any consolation, GTO wheels (with their larger center bore hole) will fit, no problem. Plus, BMW wheels (with their larger bore holes) will also fit. Their are tons of styles of wheels for BMWs.

Not really. Most GTO owners are running from +40 to +48 with no problem. Give it 2-3 months & people will be testing & coming up with reliable wheel & tire combos.
True, most of us run +40 to +45mm, my Holden C4 wheels were +45 and fit perfect. I called my wheel guy today and he said they have a limited selection so far. Since I'm getting the 19's on my ride, I decided to just send them off to my powdercoaters and have them do them in a black chrome finish like the Goat wheels.
Mine:
http://i136.photobucket.com/albums/q184/sloloco/CIMG2974.jpg
The future ride's:
http://i136.photobucket.com/albums/q184/sloloco/CIMG3006.jpg

im selling mine, thatd me mean on a g8 st. beyern 5's in 19s anyone

im selling mine, thatd me mean on a g8 st. beyern 5's in 19s anyone

I am lost ?

I think that he said he's selling his 19s, for some others.

im selling mine, thatd me mean on a g8 st. beyern 5's in 19s anyone

I can get you 19" Beyern 5's for $250ea. I think.

I'm going to run a set of VE GTS's if I can get them shipped for under a $1000 from Australlia :(

I can get you 19" Beyern 5's for $250ea. I think.

I'm going to run a set of VE GTS's if I can get them shipped for under a $1000 from Australlia :(

Are you talking about shipping price for less the $1K? Or price of the wheels for $1K? If the GTO is any indication, you will need a bigger wheel budget. Are you talking about HSV GTS wheels? I'm gonna guess about $3,500. including shipping.

I'm going with some HSV wheels but still ordered my car with the 19's because it was such a cheap bump. You cant find a nice set of 19" wheels and tires for under $1500, even my cost! Now if I could just figure how mit to get raped on freight for my Holden wheels?!:confused:

I see members starting to put after market wheels on their G8, but I still don't see wheel specs. I think we need some real numbers so we can make a Sticky with wheels specs. I see a lot of wheels that I like but want narrow down which will/will not fit.

"a little Photoshop action here"
http://i228.photobucket.com/albums/ee296/polefighter/crop14.jpg

I'm going with some HSV wheels but still ordered my car with the 19's because it was such a cheap bump. You cant find a nice set of 19" wheels and tires for under $1500, even my cost! Now if I could just figure how mit to get raped on freight for my Holden wheels?!:confused:

if you find a way to avoid a shipping raping, please let me know! I want HSV wheels, too!

I was told by discount tire that the wheel specs are the same as the '08 CTS. Not sure if that is true. They told me that ideally for me to not change tires as well I would need a 19x8 wheel with a +40 offset.

I see members starting to put after market wheels on their G8, but I still don't see wheel specs. I think we need some real numbers so we can make a Sticky with wheels specs. I see a lot of wheels that I like but want narrow down which will/will not fit.
I posted most of the specs in this thread. Plus, more threads come up each day asking a question that has been answered a dozen times before. As for a definative "what will/won't work" sticky may not do as much good as you would think. Some GTOs had misaligned subframes. So, wheel/tire combos would fit perfectly on one side & rub on the other. Plus, tire brand & size have an effect on what works & what doesn't.
I was told by discount tire that the wheel specs are the same as the '08 CTS. Not sure if that is true. They told me that ideally for me to not change tires as well I would need a 19x8 wheel with a +40 offset.
Since I haven't been on any CTS forums or had a new one in my shop, I checked Tire Rack's site. They show 5x120, just like the G8. As mentioned above, many factors go into finding what fits when buying wheels and/or tires. The +40mm offset is a baseline. The defining factors will be those that jump in to get wheels & do the test fitting. They will start to go wider, get different offsets, blah, blah, blah.

I was told by discount tire that the wheel specs are the same as the '08 CTS. Not sure if that is true. They told me that ideally for me to not change tires as well I would need a 19x8 wheel with a +40 offset.

The CTS wheels shown on Tire Rack's website do not show staggered fitments so let's hope you are wrong on this. I want to see at least a 285 (if not a 295) in the rear.

The CTS wheels shown on Tire Rack's website do not show staggered fitments so let's hope you are wrong on this. I want to see at least a 285 (if not a 295) in the rear.
I didn't get into a staggered setup option with them. When I asked I said I wanted it exactly as is but different wheels. Like the post above you says it's just gonna be a baseline. I called a couple of other places and they all told me the same offset #'s.

The CTS wheels shown on Tire Rack's website do not show staggered fitments so let's hope you are wrong on this. I want to see at least a 285 (if not a 295) in the rear.

I expect a 295 tire will be on someone's car in less than 3 months. BTW, Dodson the factory wheel offset is +48. Again, not sure of the CTS. Could be the same bolt pattern but different offset from the factory.

I expect a 295 tire will be on someone's car in less than 3 months. BTW, Dodson the factory wheel offset is +48. Again, not sure of the CTS. Could be the same bolt pattern but different offset from the factory.

Thanks for the info. I ordered from Group A Wheels. They had the wheels specifically for the G8 so I am trusting in them to get all of that stuff right.


*crosses fingers

Thanks for the info. I ordered from Group A Wheels. They had the wheels specifically for the G8 so I am trusting in them to get all of that stuff right.


*crosses fingers

If it makes you feel any better, ROH wheels are made in Australia. So, I'd say that company knows their Commodores.

If it makes you feel any better, ROH wheels are made in Australia. So, I'd say that company knows their Commodores.

Honestly, I am not worried about the fitment at all. I researched them and saw that most everyone was VERY happy with them.

I am much more concerned about how long it will take for them to arrive. LOL I want them now! :bubbrubb:

Honestly, I am not worried about the fitment at all. I researched them and saw that most everyone was VERY happy with them.

I am much more concerned about how long it will take for them to arrive. LOL I want them now! :bubbrubb:

Well, since you've sprung for the wheels, what brand & size of tires have you chosen? I don't think you listed the whel sizes either. ;)

Well, since you've sprung for the wheels, what brand & size of tires have you chosen? I don't think you listed the whel sizes either. ;)

I got the 19x8 Drifter-R's in black. I am hoping that I can just take the stock tires off and put them on the new wheels.

Please don't tell me they won't fit. LOL I was trying to get around buying tires.

I got the 19x8 Drifter-R's in black. I am hoping that I can just take the stock tires off and put them on the new wheels.

Please don't tell me they won't fit. LOL I was trying to get around buying tires.

As long as you got the Sport package that comes from the factory with 19" tires. Sounds like you're not gonna go with a staggered setup....yet. ;)

As long as you got the Sport package that comes from the factory with 19" tires. Sounds like you're not gonna go with a staggered setup....yet. ;)

I have the 19's. I kind of did want to go with a staggered setup but I didn't see that wheel available like that. I may look into it later on.

I posted most of the specs in this thread. Plus, more threads come up each day asking a question that has been answered a dozen times before. As for a definative "what will/won't work" sticky may not do as much good as you would think. Some GTOs had misaligned subframes. So, wheel/tire combos would fit perfectly on one side & rub on the other. Plus, tire brand & size have an effect on what works & what doesn't.

Thanks sccaGTO, I've read your post about the offset, I understand now. There are different offsets (+40 thru +48) that will work depending size of wheel/tire & brand used. Now we have to concerned about the Speedometer when we plus size.

Thanks sccaGTO, I've read your post about the offset, I understand now. There are different offsets (+40 thru +48) that will work depending size of wheel/tire & brand used. Now we have to concerned about the Speedometer when we plus size.

Not really a problem with plus sizing. The big catch is to get a tire with the new diameter wheels that will be close to the old combination's tire overall height. For example, the stadard tire size is P245/45R18. Most tire companies list the tire's overall diameter as ~26.7". The Sport package has size P245/40R19. Most tire companies list that tire as ~26.7" tall. If you plan to keep the first number (tire width measured sidewall to sidewall-not tread width), then the middle & last numbers can be adjusted with no big problems. In the 2 sizes listed for the G8, when you move the diameter of the wheel (the last number in each size) up, you move the middle number down. That middle number is called the aspect ratio. Key in on the "ratio" part. The easy way of saying that is the middle number is the height compared to the width. Basically, for each inch that the wheel diameter goes up, the ratio will go down one point. Aspect ratios are always in increments of 5 (40, 45, 50, etc.)

P245/45/18 ~ P245/40/19 ~ P245/35/20

Now, if you do wider wheels/tires in the rear, then you had better get a drink. That may take a little while. :popcorn2:

Has anybody tried to actually measure the hub bore? Anybody have a micrometer?

I asked an Aussie member on another forum & the response is 67.5mm bore size. It is 2mm smaller than the previous VZ Commodore & GTO.