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YOUR RESEARCHTire size options on 40th anniversary?
Leading reported evidence
Use 285/30/18
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I think the C4S and 40th used the 295/30/18 tires, while the standard Carrera used 285/30/18 - but that is part of the mystery I'm trying to solve.
Leading evidence: 'Use 285/30/18' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'ps4s' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Run 235/40/18 front and 295/30/18 rear' (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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I think the C4S and 40th used the 295/30/18 tires, while the standard Carrera used 285/30/18 - but that is part of the mystery I'm trying to solve.
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The 40 used the same wheels as the other 2004 Carrera coupes on 18 inch rims , the are just polished carrera 2 lightweights .
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Suspected cause
Since our speedos tend to report more MPH than actual, I suspect the PS4S with the 285/35 thicker sidewall will get you a more accurate speedo.
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Suspected cause
I suspect speccing 295's to our cars was driven by the marketing team vs the product team at the time of launch.
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Suggestion
I have an 02 C2 and have been running multi-sets of the stock size 285-30-18 tires on the rear but just like all of us, having a difficult time finding tires, and have been eyeballing moving to 285-35-18 in the rear, or even 295-30-18.
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Suggestion
I thought I had read a previous thread on people running PS4's on 996's, I need new tires on my car this year and planned to try the PS4's but didn't realize they didn't have the 30 ratio rear
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It is time for new rubber on my 40th.
I am going to go with Michelin.
With the stock rims, I am limited to PS2�s (225-40-18, 285-30-18). There are few tire options in these sizes.
I can purchase Pilot Sport 4S in the following sizes - 235-40-18 and 285-35-18.
The diameter difference is 1.7%
I would rather get the latest Michelin tires rather than the PS2 that may have been manufactured a year or more ago.
Any thoughts or concerns with these sizes?
Thanks
i have the 285-35-18 and it can cause ABS faults due to the diameter being too big, especially if say the front tire pressure is low and rear is high, etc. I would not recommend tires that tall.
The 40 used the same wheels as the other 2004 Carrera coupes on 18 inch rims , the are just polished carrera 2 lightweights .
go on tire rack's website enter your car and click on the 18" and you'll find all manner of options . From track tires to daily use
https://www.tirerack.com/tires/TireSearchResults.jsp?tireIndex=2&autoMake=Porsche&autoYear=2004&autoMod el=911+Carrera+Coupe&autoModClar=&frontWidth=225%2F&frontRatio=40&frontD iameter=18&frontSortCode=53650&rearWidth=285%2F&rearRatio=30&rearDiamete r=18&rearSortCode=54500
im running dunlop direzza zii star spec tires
The best time to look for tires is in the late spring , tire rack has more options from more manufacturers then .this time of the year you get good run out pricing but less options as the manufacturers make limited numbers of 911 sizes .
i also have a set of winters and rims I bought from them in the same size
Sorry to resurrect this old thread, but I'm shopping for tires for my 40th. What is on my car today are Sumitomo 295/30/18 in the rear and 225/40/18 in the front. The manual says 225/40/18 front and 285/30/18 rear "or" 225/40/18 front 295/30/18 rear. There is nothing special indicated for the 40th, but I read somewhere that these cars originally came with Pirellis unique to the 40th. To further confuse matters, different tire fitting sites (Michelin, tire rack, etc.) show different combinations, including 235/40 for the fronts.
I'm a little reluctant to go back to Sumitomo because one rear tire has a blistered inner side wall (tires have 10k miles in 10 years). Anyone know what was originally on these cars - or am I overthinking this? Also might be worth noting that the speedo reads a few mph high, so that makes me reluctant to go to 285s in the rear.
I've been running 235/40/18 front and 295/30/18 rear for about 5k miles now and not a single issue. I would actually like to try 285/35/18 in rear next time as I'd like some extra sidewall there. Pretty sure there are some members that have ran this set up. I went with General G-Max at the time and have been very happy. I'd like to try some Michelin rubber in future.
I thought I had read a previous thread on people running PS4's on 996's, I need new tires on my car this year and planned to try the PS4's but didn't realize they didn't have the 30 ratio rear
You should be ok with PS4's as there are members here running
285/35 in the rear on the same wheels. This is less of an issue for us with a C2 than a C4. Yeah, your speedo may be off a bit but I can live with that.
Out of curiosity, I looked into the specs of the Pilot Sport 4S relative to the Pilot Sport 2 for rear tires
PS4S: 285/35/18 has 25.9" diameter, 804 revs per mile. At 800 RPM for the wheel, speed would be 59.7 MPH (I know the math isn't really that simple)
PS2: 295/30/18 has 25.5" diameter, 817 revs per mile. At 800 RPM speed would be 58.8 MPH
PS2: 285/30/18 has 24.8" diameter, 840 revs per mile. At 800 RPM speed would be 57.1 MPH
Since our speedos tend to report more MPH than actual, I suspect the PS4S with the 285/35 thicker sidewall will get you a more accurate speedo. Maybe Porsche calibrated the speedos based on tires delivered. I think the C4S and 40th used the 295/30/18 tires, while the standard Carrera used 285/30/18 - but that is part of the mystery I'm trying to solve.
The PO of my car installed 285 rears on my 40th and it drives fine, any 996 should run fine with either 285 or 295's fitted. I suspect speccing 295's to our cars was driven by the marketing team vs the product team at the time of launch. After doing some more research I'm going to go PS4S on my 40th this summer, its a superior tire and that extra sidewall can only help absorb some of the MN broken up roads
Knfeparty,
Thanks for insight. Anybody else have this issue.
I have an 02 C2 and have been running multi-sets of the stock size 285-30-18 tires on the rear but just like all of us, having a difficult time finding tires, and have been eyeballing moving to 285-35-18 in the rear, or even 295-30-18.
Any feedback on ABS issues, handling characteristics, or anything, from anyone running either would be greatly appreciated.
Thanks!
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