You gave only one size. The 355 has different tyre size front and rear. You have to see the chart to see the correct conversion to the 20in rims. But whay would you want to increase up to 20in. The tyre profile will be so thin that it will be uncomfortable.
I suggest you only do one size increase to 19in. The Challenge Stradale uses 19in rims.
It is supposed to be a show car. I have the rims laying here, but havent got the car yet. Yes they are chrome and bling bling and un comfy, but as a show prospect it works superb. Just wondering if it fits. Is the outer diameter different form front to rear on the 355? Then I guess I`ll get problems with the car\tire combo. All my wheels are 245/35-20". What will happen if they arent the same. My Benz started to struggle with the ASD,ASR and so on when i gave it different size up front and at the rear. Will the same thing happen to a Ferrari with similar size front and rear? Thanks.
Here is an idea; spend the money and then let us know how it worked out. Or B) ask a wheel shop. No one on here has ever tried this for a reason so you will not find an answer from any of use. Sorry we just don't know.
I was very tempted to put this topic in File X. But because Stradale made a good comment that is worth keeping for future searches I'm just going to lock this topic. Sorry we couldn't help, let us know how the 355 search goes and stay away from illegal garbage because that is what it is.
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