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18x8.5 and 18x11 on a C4S?

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YOUR RESEARCH18x8.5 and 18x11 on a C4S?

Leading reported evidence

Run 10mm spacer up front and a 18mm offset

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Unsuccessful attempts: 1
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For reference, on stock wheels on my turbo I ran a 10MM spacer up front and a 18MM offset on the rear.
Original post Read captured discussion
18x8.5 and 18x11 on a C4S?

Frequently discussed work

Adjust offset accordingly

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Unsuccessful attempts: 1
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Suggestion
Obviously you can go with wider wheels (8.5" instead of 8" in the front for example), but will have to adjust your offset accordingly.
Original post Read captured discussion
18x8.5 and 18x11 on a C4S?

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Leading evidence: 'Run 10mm spacer up front and a 18mm offset' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Adjust offset accordingly' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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Adjust offset accordingly

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Suggestion
Obviously you can go with wider wheels (8.5" instead of 8" in the front for example), but will have to adjust your offset accordingly.
Original post Read captured discussion
18x8.5 and 18x11 on a C4S?

Replace current 19s

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

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Suggestion · Original poster
I wanted to go back to 18s to replace the current 19s.
Original post Read captured discussion
18x8.5 and 18x11 on a C4S?

Frequently discussed actions (3)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Adjust offset accordingly

No successful repair reported for this finding.

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Reported fixes: 0
Unsuccessful attempts: 1
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Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

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Suggestion
Obviously you can go with wider wheels (8.5" instead of 8" in the front for example), but will have to adjust your offset accordingly.
Original post Read captured discussion
18x8.5 and 18x11 on a C4S?

Replace current 19s

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster
I wanted to go back to 18s to replace the current 19s.
Original post Read captured discussion
18x8.5 and 18x11 on a C4S?

Run 10mm spacer up front and a 18mm offset

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that performed work without a confirmed outcome: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed
For reference, on stock wheels on my turbo I ran a 10MM spacer up front and a 18MM offset on the rear.
Original post Read captured discussion
18x8.5 and 18x11 on a C4S?

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Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

4 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

Rennlist: 1 discussions

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Generation: 20261027T031046Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

So I've voiced my novice knowledge on wheel/tire sizes and off sets on here in the past and need some assistance prior to a potential purchase. I'm close to closing the deal on a set of Champion RG5's for my 2005 C4S. The sizes are: 18x8.5 et 50 and 18x11 et 60. I assume I'm going to need spacers on at least the fronts? If so, what size? Rears seem very close to the OEM specs. I wanted to go back to 18s to replace the current 19s. Any assistance in this area would be greatly appreciated. Thanks in advance.

POST 2Original post

rear offset is all wrong, will need spacers. Stock C4s and Turbo offsets are as follows 8x18 50mm, 11x18 45mm For reference, on stock wheels on my turbo I ran a 10MM spacer up front and a 18MM offset on the rear.

POST 3Original post

Yep, you don't want those, you'd need big spacers on the rear, makes a lot more sense to just buy the right sized wheels for your car. Taking the stock sizes and adding in "soon2be..."'s experience, you wanna look for: A front wheel that is 18x.8" with an offset in the range of 50~35 A rear wheel that is 18x11" with an offset in the range of 45~27 As you move closer to the lowest number in the above offsets, you push the wheel further out meaning you might have some rubbing on the fender lip, some poke, and ultimately some road rash on the rear of your front and rear fenders. Obviously you can go with wider wheels (8.5" instead of 8" in the front for example), but will have to adjust your offset accordingly. Hope that helps.

POST 4 / ORIGINAL POSTEROriginal post

That helps a lot. Thank you much.

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