Planet-9

40 series tires on 19 inch wheels 987.1

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YOUR RESEARCH40 series tires on 19 inch wheels 987.1

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Run 40 profile

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Suggestion
Running the 40 profile on the 19's will mean that the speedo reads incorrectly though ?
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40 series tires on 19 inch wheels 987.1

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Run 40 profile

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Suggestion
Running the 40 profile on the 19's will mean that the speedo reads incorrectly though ?
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40 series tires on 19 inch wheels 987.1

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POST 1Original post

A friend just bought a 987.1 Cayman S with lobster claw 19" wheel and PASM . Very harsh ride with the 35 series 19s. Wants to go with 40 series (235 & 265) on the 19" wheels. Has anyone tried this without PSM going off because it's over a 3% tire diameter change? Any tire to strut interference requiring wheel spacers? thx

POST 2Original post

Things are pretty tight in the 987.1 wheel well, I'd think there would be a good chance of rubbing. And yes, PSM would be a problem. Probably smarter to just change to 18" wheels.

POST 3Original post

From experience I understand what you mean by the 19” wheels being a bit rough on the 987.1 cars. 18” wheels would be the best solution to the problem. However if you stay with 19” wheels , PSM shouldn’t have a problem if the diameter of the front and rear tires is the same front to rear. Really shouldn’t matter what series (35, 40, etc) the tires are. Fitting in the wheel well, as noted above, is probably more important.

POST 4Original post

Running the 40 profile on the 19's will mean that the speedo reads incorrectly though ? A larger diameter will mean that the car will be travelling faster than the indicated speed, a tyre size comparison tool will tell you by how much ? Having recently swapped my 987 'S' from 19's to 18's to improve the ride quality, I would suggest that this is a better idea than putting a non standard tire size on the 19 inch rims.

POST 5Original post

I put 40’s on my 2009 987.2 without any issues

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