STS 18" 9 Spoke Rims on my CTS

9980 Views 32 Replies 18 Participants Last post by z06bigbird, Jul 1, 2007

tomm

Discussion Starter · Jul 21, 2005

After all the calculations and threads over offsets and tire sizes what it comes down to is this. The STS 8" Rims do not look good with a 225/45 size tire since the tire when installed almost looks thinner than the rim. 245/45 is definately the perfect size for this rim but there is a problem. Once installed there is around a 1mm space between the pinch bolt and the tire. So yes it fits but with 1mm or less space its not a safe install. I had trouble getting 6 sheets of paper between this space so it might even be smaller than 1mm.

I am bringing the tires to the shop tomorrow morning to have them look at it and see what we can do. When speaking with the shop they said that if I use a spacer more than 1/4" I will need new bolts installed but once I do that I would most likely have issues with the GM warranty on any of the brake components.

I definately love the look of these rims and I will do what it takes to get them on the car and I am hoping that a 1/4" spacer will do the trick. Here is a picture of the front rim installed right before I had removed it. My son wanted to be in every picture I tried to take so I gave up trying to take a picture without him.

What do you think?

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1 - 20 of 33 Posts

J.E.T.

· #2 · Jul 21, 2005

Very nice......I'd be nervous about trying to make something fit however........

JET

Oversized CTS

· #3 · Jul 21, 2005 (Edited)

Looks good from this angle. :thumbsup:

Can't wait for more pics once you get the spacing issue resolved

tomm

Discussion Starter · #4 · Jul 21, 2005

J.E.T. said:
Very nice......I'd be nervous about trying to make something fit however........

JET

Per Pete from Cadillac Motorsports

"Regardless of wheel size; 225 or 245; wheel spacers are always a good idea and highly recomended as "one of the purposes" of a spacer is to prevent wheel runout and vibration as even a 5 x115 bolt pattern causes the wheel hub to rest directley on the hub bolts which is never a good idea. Even the smallest spacer (1/16"th billet) on a 225 series wheel rim that is machined to be both wheelcentric and hubcentric will avoid this problem by properly "centering or balancing" the wheel hub so the wheel rim does not rest directly on the lugs. You will also be able to retain your same lug bolts without any changes due to the small diamete of the 1/16'th spacer Check out this website: www.cromec.com for more information. The bottom line is that you NEVER want to use your wheel lug bolts as a centering device for torqueing down your wheels as you will eventually develop runount, front end vibration and shimmy. Porsche installs hubcentric and wheel centric spacers on most all 911's before they leave the factory for this exact reason."

I value his opinions and if my shop can not supply these I will see if Pete can make some up for me.

Tom

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Smokin' 04 CTS

· #5 · Jul 21, 2005

I installed 20's on my CTS and it has 245/35/20.. I had spacers put on in the front to get the rim to clear the brake caliper. I noticed that bolt you mentioned, but I never had any issues with that. I am actually going back to get rear spacers put in to balance out the front with the rear.

Sorry to hi-jack this thread, but has anyone heard of "knuckles"?? Its because I am putting those on my rear springs to reduce spring compression. Reason is, is that when people ride in the back and I go over a bump, the rear tires rub...

-1-

· #6 · Jul 21, 2005

:hmm: Tom, the STS wheels look great. I agree, I would rather the wheels fit without a spacer, the same with our CTS. Per Pete from Cadillac Motorsports, if that's the case why don't they come with spacers from the factory? When I needed spacers, I found that most automotive stores don't sell them. Most people say they're against the law, I don't know. It also becomes an issue when you get your vehicle state inspection. I asked the guy who did our inspection and he said no problem. From what I've heard, hub centric spacers are the best. I'm sure you wont be able to get a 1/4" hub centric spacer made due to the spacing on the hub. That's what I was told when I had mine made. You could go with 1/4" non hub centric spacers. If you go with anything larger than 1/4", you'll have to change the lug bolts. Most wheel spacers you'll find are generic, fit many bolt patters. There are many people on ebay that will custom make spacers to your specs. That's what I'd recommend. The 18" STS wheels and the larger 245X45X18 tires look great. I've had the spacers on our CTS without any problems with vibration or tire wear. Your close to achieveing that unique look.

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tomm

Discussion Starter · #7 · Jul 21, 2005

-1- said:
:hmm: Tom, the STS wheels look great. I agree, I would rather the wheels fit without a spacer, the same with our CTS. Per Pete from Cadillac Motorsports, if that's the case why don't they come with spacers from the factory? When I needed spacers, I found that most automotive stores don't sell them. Most people say they're against the law, I don't know. It also becomes an issue when you get your vehicle state inspection. I asked the guy who did our inspection and he said no problem. From what I've heard, hub centric spacers are the best. I'm sure you wont be able to get a 1/4" hub centric spacer made due to the spacing on the hub. That's what I was told when I had mine made. You could go with 1/4" non hub centric spacers. If you go with anything larger than 1/4", you'll have to change the lug bolts. Most wheel spacers you'll find are generic, fit many bolt patters. There are many people on ebay that will custom make spacers to your specs. That's what I'd recommend. The 18" STS wheels and the larger 245X45X18 tires look great. I've had the spacers on our CTS without any problems with vibration or tire wear. Your close to achieveing that unique look.

1/4" should be plenty of space and I am not worrying about inspections since my cars next inspection would be in 2009. (New cars do not need to be re-inspected in NJ for 4 years.) I've done alot of reading on this subject and it looks like spacers are very common. If the shop has some cheap ones I will probably pick them up and get the STS rims on the car and I will order some custom made hub centric ones from Pete for a permanent installation.

J.E.T.

· #8 · Jul 21, 2005

Hmmmm, now you've got me wondering if the STS wheels I have now (17") need a hub spacer also. Pete commented on my "tire balance" thread also so he's aware of my situation now. I dunno, I don't like spacers of any kind and want a wheel to fit tight against the hub.........

JET

tomm

Discussion Starter · #9 · Jul 21, 2005

I was at the tire shop for almost 2 hours this morning and they were kind enough to let me in the shop area to look at the car on the lift with different size spacers. I have decided against using these Rims on my CTS because there are too many issues. To correct the offset to match the CTS I would need slightly longer than 1/4" and once I do that the fenders rub so I would need to roll the fenders. I will wait for these rims to come out for the CTS which should be shortly. They will be in a 7 1/2 rim size which would be correct for the CTS.

odysseus

· #10 · Jul 21, 2005

Tomm,

Are these STS wheels 51mm offset? If the new CTS wheels are still 51mm offset, you'll still have the same problem with 245's. 1/4" spacers are roughly 6.5 mm. This would make the effective offset of those wheels 44.5mm (51-6.5). The Vauss wheels have 44mm offset, and they come with 245s. The V comes with 42mm offset. My wheels have 40mm offset, which is less than half inch difference from the stock CTS.

1/4" spacers should be plenty. My biggest concern would be having at least three or four turns of thread engaging on the lugnuts after adding spacers.

tomm

Discussion Starter · #11 · Jul 21, 2005

odysseus said:
Tomm,

Are these STS wheels 51mm offset? If the new CTS wheels are still 51mm offset, you'll still have the same problem with 245's. 1/4" spacers are roughly 6.5 mm. This would make the effective offset of those wheels 44.5mm (51-6.5). The Vauss wheels have 44mm offset, and they come with 245s. The V comes with 42mm offset. My wheels have 40mm offset, which is less than half inch difference from the stock CTS.

1/4" spacers should be plenty. My biggest concern would be having at least three or four turns of thread engaging on the lugnuts after adding spacers.

The new CTS 18's will be 7.5" and the tires will be 225's which will leave plenty of room. The way the 8.0" rim is designed the 225's would not look correct on these rims. Using 1/4" spacers on these STS rims I saw the tire and they put quite a bit of pressure on the rim to simulate a hard turn and the wheel does flex and it can rub against the pinch bolt. The installer had nothing to gain either way but when I asked him if it was his car would he use them his answer was "Definately Not"

At the same time with the spacers the tires did rub the fenders because they were sticking out almost a inch more than the stock tires. Safety is a big concern for me since I usually travel with my <2 year old in the back seat.

PAW 47

· #12 · Jul 21, 2005

Tom,

Silly question why not just use 235/45/18's? They have a few brands..in that size they also have them in 235/40 as well..

tomm

Discussion Starter · #13 · Jul 21, 2005

PAW 47 said:
Tom,

Silly question why not just use 235/45/18's? They have a few brands..in that size they also have them in 235/40 as well..

A different size tire would prevent the fender from rubbing but the rim itself was too close to the control arm itself (Not just the pinch bolt). We are talking we could measure the space with cat whiskers. I can now see why its suggested that you go no more than a 40-45mm offset on an 8" rim. 51mm on an 8" rim is no good for a CTS.

spaceman78

· #14 · Jul 21, 2005

Hello I Have A 2004 Cts With The Factory 17 Inch Polish Mirror Wheel....The Car Looks Great With That Rim........Forget All This Stuff About 18 Inch Rims Spacers Long Lug Nuts LOl...........Wainte For The 2006 CTS 18 inch Weel.... Good Luck God Bless.....

The Tony Show

· #15 · Jul 21, 2005

How about trading me for a set of STS 17in polished wheels with 255 rear/235 front Michelin HXMXM4 tires?

7000 miles on the rubber, no curb damage (or any damage) to the wheels, no vibrations in the tires. PM me if you're interested.

-1-

· #16 · Jul 21, 2005

:yup: Tom, sorry the 18" STS wheels didn't work out. Great effort!

tomm

Discussion Starter · #17 · Jul 22, 2005

Tony Orlando said:
How about trading me for a set of STS 17in polished wheels with 255 rear/235 front Michelin HXMXM4 tires? 7000 miles on the rubber, no curb damage (or any damage) to the wheels, no vibrations in the tires. PM me if you're interested.

I have no interest in 17's. I actually bought a set of those a few months back and I sold them to a forum member for $400. I already have a buyer for $800 for the Rims without the tires and I had no problem returning the tires. I still like the design alot and I will buy them as soon as I see a set of the CTS 18's hit the streets with the correct offsets.

RobertCTS

· #18 · Jul 22, 2005

tomm said:
After all the calculations and threads over offsets and tire sizes what it comes down to is this. The STS 8" Rims do not look good with a 225/45 size tire since the tire when installed almost looks thinner than the rim. 245/45 is definately the perfect size for this rim but there is a problem. Once installed there is around a 1mm space between the pinch bolt and the tire. So yes it fits but with 1mm or less space its not a safe install. I had trouble getting 6 sheets of paper between this space so it might even be smaller than 1mm.

I am bringing the tires to the shop tomorrow morning to have them look at it and see what we can do. When speaking with the shop they said that if I use a spacer more than 1/4" I will need new bolts installed but once I do that I would most likely have issues with the GM warranty on any of the brake components.

I definately love the look of these rims and I will do what it takes to get them on the car and I am hoping that a 1/4" spacer will do the trick. Here is a picture of the front rim installed right before I had removed it. My son wanted to be in every picture I tried to take so I gave up trying to take a picture without him.

What do you think?

I agree Tomm...He's a cute kid!

Oh..rims are O.K. but a real pain in the @ss.

D148L0

· #19 · Jul 22, 2005

The rims look good, and you have a good looking little fella. :thumbsup:

dbknight

· #20 · Jul 22, 2005

Will I have any issues putting the 17" 05's on my 03 which came with 16"s?

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