tire rubbing issues

[cutlass supreme FE3]

On my 88 Cutlass the stock tire size is 215/65/15 while on the 89 they were 225/60/16.
I have upgraded to the 89 16 inch mag wheels and 235/60/16 Nokian Hakkapelitta snow tires and at full turn the front wheels are rubbing something in the fenders.

I was informed going one size wider would not give any issues.

[IsaacHayes]

You can go one side wider perhaps, but if you don't reduce the side wall to width ratio number, then you are also going to a taller tire as well.

Your 235/60/16's are 27" diameter, roughly 1 inch bigger than 215/65/15 or 225/60/16.

Taller than stock (which will throw off your speedometer, and reduce your gear ratio, making your car reach a higher speed than normal before it shifts, and also you will be going faster than what your speedometer reads) will also rub of course.

You need 235/55/16 to keep the same diameter tire.

And when driving in the snow you want a NARROWER tire than what you would normally run in summer. So you would want to keep 215, or even smaller if the car wouldn't be dangerous. So by going 20mm wider, you have essentially made the car grip worse in snow. On my car, I run 225/50/16. Stock tire is 205/55/16. In the winter, I swap to 14" wheels with 185/75/14. All those 3 tires are the SAME diameter so there is no issues there. I tried all season 205's brand new in light snow and they were worthless. So I went to a wider 225 for summer and then use the 185 on cheap steel wheels for winter. The 185 are not a snow tire, but since they are narrow, it works great. They are a bit narrower than what the car calls for (195min) but my suspension is built up and I just drive them in winter when I'm going slow anyways. It cuts through the snow to the pavement, with more pressure per inch, than a wide tire. Think of a wide tire just floating on top of the snow like a big tabagon or trash can lid sliding down a hill. Now get a narrow tire and it cuts down instead of floating on top...

So sorry to break it to you, but those tires are the wrong size to fit the spec of your car, and to work well in snow...

You should run 235/55/16 in summer and 215/65/15 in winter.

Whenever you go a wider size (first #) or a bigger rim (last #) you need to reduce the middle number to keep the same overall diameter.

[IsaacHayes]

https://www.miata.net/garage/tirecalc.html

[cutlass supreme FE3]

yeah your are correct.
I have upgraded to stock 89 cutlass international wheels and the OEM tiressize on those cars is 225/60 16.
So the difference from 225/60/16 to 235/60/16 is 0.5 inch in diameter.

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
215/65-15 5.5in 13.0in 26.0in 81.7in 776 0.0%
235/60-16 5.6in 13.6in 27.1in 85.1in 744 4.2%
235/55-16 5.1in 13.1in 26.2in 82.2in 770 0.7%
225/60-16 5.3in 13.3in 26.6in 83.7in 757 2.4%