How wide can you go on Rear rim width??
#16
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Just an FYI.
If you select the Sport Techno wheels that are 11.5" wide in the rear, Porsche does not allow you to use the 5mm spacer (1/4"). So, in a way, Porsche is saying the widest rear tire you can use is 11.5".
If you select the Sport Techno wheels that are 11.5" wide in the rear, Porsche does not allow you to use the 5mm spacer (1/4"). So, in a way, Porsche is saying the widest rear tire you can use is 11.5".
#17
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Well your original question was how wide can you go? Sport Techno's are 9 & 11.5x20 and look great. But can you fit wider? Of course. The question is, why? And why ask only about the rear?
Odds are you're going for looks. But here's the thing about appearances. There's the reaction of the average guy who knows nothing and assumes lower/wider=faster/better. So you stuff as much as you can in there that guy is impressed. Then there's the guy who knows Porsches. I'm talking about the DI who the first time he saw my car after corner-balancing said Hey you got your car set up- looks great! Now I know for a fact the measurements changed at most a few mm but this guy spotted it immediately and knew.
Which one are you going for?
Odds are you're going for looks. But here's the thing about appearances. There's the reaction of the average guy who knows nothing and assumes lower/wider=faster/better. So you stuff as much as you can in there that guy is impressed. Then there's the guy who knows Porsches. I'm talking about the DI who the first time he saw my car after corner-balancing said Hey you got your car set up- looks great! Now I know for a fact the measurements changed at most a few mm but this guy spotted it immediately and knew.
Which one are you going for?
#18
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Thank you Chuck, I am going more for looks. One day I hope to have a car primarily dedicated to track use. When that occurs, I will most certainly consider the correct equipment so I can obtain the fullest potential out of my car. For now, I drive my car 99% on public roads and play with it occasionally. I think we can all agree that the full capabilities of this car cannot be witnessed on public roads. I will likely be taking this car to the track, but only for fun, and if it happens more than twice a year I would be surprised. FRom what I have gathered, 11.5 x 20 is the max.
Next thing up, tire size. Going from 11 to 11.5 does NOT require a different size tire. Please note on Porsche website they fit two different tire sizes to the same Sport Techno wheel, with the wider tire going on the C4S, but that's more marketing than anything. The wider tire looks a tiny bit beefier which goes better with the wider C4S body. Seriously. You can run either size just fine on either car. In terms of handling and feel, going wider gives a bit more comfort, a bit slower response. But I doubt you'd feel the difference this is something more noticeable when moving three or 4 cm not the 1 cm we're talking about here.
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This was one of the reasons I selected the Sport Techno wheel for my build, because I wanted the 305 tire on my C2S and liked the wheel better, as a plus.
#20
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All sport techno tires for s and 4s rear are 305's in the rear. The rest of the (stock Porsche) rear rims for 4s are all 305's but for the s are 295's. They have different offsets (the ET number) for the same style rims for s vs 4s. So, a s rear sport techno rim will either not fit or not look right on a 4s because of the offset.
Sport Techno wheels
Size: Carrera/Carrera S
Front - 9 x 20 ET51 - 245/35 ZR 20
Rear - 11.5 x 20 ET68 - 305/30 ZR 20
Size: Carrera 4/Carrera 4S
Front - 9 x 20 ET51 - 245/35 ZR 20
Rear - 11.5 x 20 ET48 - 305/30 ZR 20
Sport Design wheels
Size: Carrera/Carrera S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET70 - 295/30 ZR 20
Size: Carrera 4/Carrera 4S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET52 - 305/30 ZR 20
Carrera S wheels
Size: Carrera/Carrera S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET70 - 295/30 ZR 20
Size: Carrera 4/Carrera 4S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET52 - 305/30 ZR 20
Carrera Classic wheels
Size: Carrera/Carrera S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET70 - 295/30 ZR 20
Size: Carrera 4/Carrera 4S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET52 - 305/30 ZR 20
Sport Techno wheels
Size: Carrera/Carrera S
Front - 9 x 20 ET51 - 245/35 ZR 20
Rear - 11.5 x 20 ET68 - 305/30 ZR 20
Size: Carrera 4/Carrera 4S
Front - 9 x 20 ET51 - 245/35 ZR 20
Rear - 11.5 x 20 ET48 - 305/30 ZR 20
Sport Design wheels
Size: Carrera/Carrera S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET70 - 295/30 ZR 20
Size: Carrera 4/Carrera 4S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET52 - 305/30 ZR 20
Carrera S wheels
Size: Carrera/Carrera S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET70 - 295/30 ZR 20
Size: Carrera 4/Carrera 4S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET52 - 305/30 ZR 20
Carrera Classic wheels
Size: Carrera/Carrera S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET70 - 295/30 ZR 20
Size: Carrera 4/Carrera 4S
Front - 8.5 x 20 ET51 - 245/35 ZR 20
Rear - 11 x 20 ET52 - 305/30 ZR 20
#21
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Then that's a recent change. Last year they listed 295's and 305's. Either way all that changes is what Porsche delivers them with. Doesn't change the basic fact you can run either size. As indeed Porsche did just last year. Keep in mind the difference is 1 cm, a mere 2.5 mm either side of the rim, which on a 35 aspect ratio tire works out to a difference of just 3.5 mm in radius, or less than tread depth.