20" wheel issues?

Hi,

I was talking to a friend, telling him I think I want to put 20" rims on my turbo. He said that sounded like a bad idea. I said the 19'
s don't fill the wheel well enough.

He said that's because I haven't lowered it yet.

Thoughts? Experiences? Will the speedo be able to be calibrated to the 20's?

Any other foreseeable problems with this?
Please help.

Thanks!



I didn't find the right solution from the Internet.



References:
 www.6speedonline.com/forums/997-turbo-gt2/405425-20-wheel-issues.html

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