Just tried comparing my future front setup from 17x7.5 et40 225/45/17s with 18x9.5 et40 225/40/18. They wouldn't allow it. Keeps either changing wheel width or tire size. Guess it doesn't like a little stretch
Interactive wheel and tire combination calculator
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Interactive wheel and tire combination calculator.
As an example, here is a side by side comparison of my 17x8 RH AD Cups and my soon to be shod 17x7 Porsche 993 Cup IIs:
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The Cup IIs shod with 205/50s are actually 4mm larger in profile, but .8"(20mm) narrower in tread width.
But in weight is where is gets interesting:
![]()
Typically 4 pounds lighter rotational mass. Zippy and sticky.
Have fun with your wheel specs.
:wrench:
As an example, here is a side by side comparison of my 17x8 RH AD Cups and my soon to be shod 17x7 Porsche 993 Cup IIs:
The Cup IIs shod with 205/50s are actually 4mm larger in profile, but .8"(20mm) narrower in tread width.
But in weight is where is gets interesting:
Typically 4 pounds lighter rotational mass. Zippy and sticky.
Have fun with your wheel specs.
:wrench:
