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Discussion Starter #1
I see we have guys, ( and perhaps some gals) with a lot of knowledge about these cars so here’s my question ;
I’m considering buying a Classica and putting Abarth rims on it but It seems to me that replacing 16 inch rims with 17 inch would put peak horsepower at a higher speed, i.e., less wheel spin and more top speed. Do they adjust for that with transmission or differential gearing in, say, the Classica with 16‘s and the Lusso with 17s? Or Does the Classica spin tires more readily and the Luso have a higher top speed?
 

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So it all has to do with the wheel and tire diameter. If you step up to a 17" wheel from a 16" then you will need to adjust the tire aspect ratio and width to match that of your 16" wheel and tire combo. I use willtheyfit.com for all of my tire and wheel spec calculations. The classica wheels and tires have a total circumference of 1889.4mm. So when you step up to a 17" wheel you would want the wheel and tire combo of that to be within 5% of that measurement. So a 215/40/r17 tire would be pretty close at 1896.9mm. Or a 205/40/r17 tire if you wanted less contact patch for more wheel spin. Hope this helps.
 

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Discussion Starter #3
Yes, it helps, Josh. Silly me for assuming that going to a larger diameter rim automatically means a larger diameter wheel overall.
So with that in mind then, I take it the Classica doesn’t corner quite as well with it’s taller side wall as the Lusso, but has a bit more pleasant or softer ride, as long as the other suspension elements are the same. Would that be a safe assumption?
 

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Yeah thats a pretty good assumption. I still dont think my Abarth rides rough but I am also still somewhat young and dont mind a firm ride.
 

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I bounce back and forth weekly between our weekend race grip setup of 17x9 and 245/40 and daily driver 16x8 with 225/50. No issues. I do it because we run really stiff springs for race weekends and the 16 inch combo softens that ride for daily driving.

The race setup....17x9:


The Daily Driver Setup.....16x8 Dekagram:

 
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