996 Winter Tyre Sizes

[Gad-Westy]

I know this topic has been covered in the past but availability of sizes seems to change almost hourly so....

Car is a 99 C4
If I go for a second set of winter wheels, I was originally going to go for Kumho winter tyres which were available in the correct 205/50/17 and 225/40/17 sizes. But they seem to be no longer available and nor seemingly is anything else. I liked the idea of 17's to give a bit more side wall on slippy stuff but not looking viable now.

If I go 18" standard sizes are 225/40/18 and 265/35/18. I can get continentals in these sizes but getting on for £700 for the set plus cost of wheels. Ouch!

Are there any recommended slight variations on tyre sizes that I should be looking at that won't bugger up the speedo and are still appropriate to standard wheel widths? Would be nice to have more options to consider.

[m444ttb]

I ended up with this problem last winter. I had some old Boxster 17s I wanted to repurpose for winter but just couldn’t find a rear tyre. In the end I went with some 18” Michelin PA4 on another sets of wheels. Ended up really expensive as you say but I figured I’d get several years from them easily.

[Scrump]

I fitted a set of 18 inch winter wheels and tyres from a 997 Carrera to my 996.
The tyres were slightly higher profile than the standard 996 ones but this actually improved the speedo accuracy!

[ATM]

Gad-Westy said:

I was originally going to go for Kumho winter tyres which were available in the correct 205/50/17 and 225/40/17 sizes.

Do you mean 255 40 17?

The 996 manual states you can use a 225 45 17 winter tyre. I believe that's right although I have not actually checked a manual - I never read manuals. Or it is on the sticker re pressures.

Anyway the point is Porsche approve use of a 225 45 17 on their factory 9 inch rears. Loads of these available.

[Gad-Westy]

ATM said:

Gad-Westy said:

I was originally going to go for Kumho winter tyres which were available in the correct 205/50/17 and 225/40/17 sizes.

Do you mean 255 40 17?

The 996 manual states you can use a 225 45 17 winter tyre. I believe that's right although I have not actually checked a manual - I never read manuals. Or it is on the sticker re pressures.

Anyway the point is Porsche approve use of a 225 45 17 on their factory 9 inch rears. Loads of these available.

Sorry. You're quite right. My notes are wrong and Kumho do still make that size front and rear. Sounds like a distinctly average tyre but not a terrible option to have. I'll take a look at the 225 45 options too. Might be academic though as wheels are proving hard to find at sensible costs!

Don't suppose you know of any 18" approved tyre size alternatives do you? My pal has a set of 18" wheels I can buy but just too much money overall if I opt for the continentals on those.

[Gad-Westy]

m444ttb said:

I ended up with this problem last winter. I had some old Boxster 17s I wanted to repurpose for winter but just couldn’t find a rear tyre. In the end I went with some 18” Michelin PA4 on another sets of wheels. Ended up really expensive as you say but I figured I’d get several years from them easily.

Indeed. Might be worth buying as they will probably work out okay in the long run but hard price to stomach at present! Out of interest, any issues with offset etc with boxster wheels? They seem much easier to come by.

[ATM]

Gad-Westy said:

ATM said:

Gad-Westy said:

I was originally going to go for Kumho winter tyres which were available in the correct 205/50/17 and 225/40/17 sizes.

Do you mean 255 40 17?

The 996 manual states you can use a 225 45 17 winter tyre. I believe that's right although I have not actually checked a manual - I never read manuals. Or it is on the sticker re pressures.

Anyway the point is Porsche approve use of a 225 45 17 on their factory 9 inch rears. Loads of these available.

Sorry. You're quite right. My notes are wrong and Kumho do still make that size front and rear. Sounds like a distinctly average tyre but not a terrible option to have. I'll take a look at the 225 45 options too. Might be academic though as wheels are proving hard to find at sensible costs!

Don't suppose you know of any 18" approved tyre size alternatives do you? My pal has a set of 18" wheels I can buy but just too much money overall if I opt for the continentals on those.

If they are 10 inch you will need a wide tyre. If you cant stomach the cost of a 265 35 you could go 255 35. If they are 9 inch from a Boxster you could stretch a 235 40 18 on to them. Or just use 4 fronts with 225 40 on all 4 corners.

[Orangecurry]

Connected to your question, Jon did a test on 16 vs 17 vs 18 inch winters, same circumference, to see if the narrower and deeper sidewall 16 is best, because established wisdom suggests it should.

https://www.youtube.com/watch?v=mhQh3IfXac0

ETA sorry - the above is a super-dooper Tyrereviews.com production

Edited by Orangecurry on Tuesday 30th November 14:14

[m444ttb]

Gad-Westy said:

Indeed. Might be worth buying as they will probably work out okay in the long run but hard price to stomach at present! Out of interest, any issues with offset etc with boxster wheels? They seem much easier to come by.

I bought them for £150 just to stand the car on while it had the st ears wheels refurbished (and with an eye to possible winter use or selling on). So all the car has done is drive in and out of the garage. They looked quite tucked in on the front compared to the standard 18” wheel. The rear wasn’t so bad. I have a picture somewhere