17 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHPorsche 996 C4S - Tire Help Needed
Reported or suspected cause
its 245-40-18 in front and 305 or 315-30-18 rears
Suggestion or failed attempt
No successful repair reported for this finding.
0
Identified cause
1
Suspected cause
0
Reported fixes
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that suspect a cause
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.
Suspected cause
I suspect its 245-40-18 in front and 305 or 315-30-18 rears.
Leading evidence: 'its 245-40-18 in front and 305 or 315-30-18 rears' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'its 245-40-18 in front and 305 or 315-30-18 rears' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Recommend fit without more work (that i'd prefer not' (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.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Recommend fit without more work (that i'd prefer not
Suggestion or failed attempt
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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
And it does not seem that anything over 25.9" is a recommended fit without more work (that I'd prefer not to do).
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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
My best thought was to run 295/35/18 rear and 255/40/18 front.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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
The suggestion has been to use 19" and 997 C4S sizes.
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.
17 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261026T135432Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hello everyone, first time poster here, spent some good time perusing but was unable to find a clear answer on my problem.
I acquired my first Porsche, a 2004 996 C4S Cab in Arctic Silver, a little over 2 months ago. Been a a fantastic time, and here's a shot
But as can be seen, I don't have the OE wheels and these seem to be Apex SM10s in an 18x9 & 18x12 setup. Running Falken 615K at 235/40 & 315/30. Tires are bit worn and I was looking to get some A/S tires for the impending winter for minimal driving as necessary. But with the rears at this setup, I'm coming up empty on options.
My best thought was to run 295/35/18 rear and 255/40/18 front. But current total diameter of tire is 25.4", and that's a massive bump up to 26"/26.1".. And it does not seem that anything over 25.9" is a recommended fit without more work (that I'd prefer not to do). Current size has summers or track tires only. Smaller sizes like 225/40/18f 305/30/18r don't have anything available it seems.
Is my only option for a decent set of A/S tires a full a new set of wheels too? Or am I missing a tire size that I can use to get A/S on these Apex wheels? My goal was to track down a set of OE Twists, but I wasn't planning to do that until next summer. Thanks for any help!
Welcome to the club.
I think a 255/40 up front would rub on the strut.
As an aside, is it possible to get close-up photos of the body plugs that are in the space between the roof lid and the engine lid? I’ve been going nuts trying to clarify which type goes there and for part numbers.
Thanks! Definitely looked like the strut would be the contact point. smaller would be ideal too. Perhaps I need to get the rear wheels off and validate that they are 12s, as they may actually be 11s?
I'll try to grab some photos for you on those body plugs. Not sure I've even looked in that space yet.
Those are pretty big wheels.
OE sizes are 8x18 in front (225-40-18), and 10x18 in rear (285-30-18).
GT3 runs 8.5 in front (235-40-18) and 11 in rear (295-30-18).
If you go to APEX's website, you can see their recommendations for the 9 and 12, 18s. I suspect its 245-40-18 in front and 305 or 315-30-18 rears. Comes down to what you can fit. If they dont fit properly, you can always sell them. They are desireable wheels.
Yeah, I found that fitment guide from Apex that recommends the 9front, 12rear. I'm assuming they read the same. Very close on tires, these are 235-40-18/315-30-18. Only thing that fits are tires I wouldn't want to be stuck in for the Winter here in CO. But some truly great track tires in this size.
Looks like the 18x12s were discontinued too. Definitely will be debating selling them. I would swap them for the OE Turbo-Look twists in 18"s, but not aware of the apex values, so I'll do some research there.
There are essentially no winter tires available to fit C4S or 996 Turbo in 18". Some people have imported tires from Canada or the EU to get the correct sizes. The suggestion has been to use 19" and 997 C4S sizes.
An update for all those who helped me out. I was able to acquire a set of base 996 wheels thanks to the ever kind
@Rossignol5
and spacers that allowed the 17" twists to fit with winters! Still need new tires but here's the end result!
Oh definitely. I was working with 2% Max from my research and had no options really. Until I got these 17s with a bigger sidewall wheel that's right on for the OEM size
I could be wrong but are SM10 available in 18x12?
For reference j put these on a 99 Carrera C218x8.5" ET45 Race Silver
APEX
SM-10 Porsche Wheel
18x11" ET60 Race Silver
APEX
SM-10 Porsche Wheel
with
235/40ZR-18 and 295/30ZR-18. Stock ride height and i love it.
Apex has a nice fitment guide.
https://apexwheels.com/fitment-guides/porsche/911
Yeah I read through all of the apex guides. The 18x12 was previously available indeed. Here's it mentioned in one of their 996 fitment guides.
Appears they no longer sell it. And it's not possible to find an all season of winter that fits this size in my research. I'll likely be selling these Apexs for a hope to get OEM 18s for mine.
