To run the NA in SCCA stock the 15" rim is limited to 5.5" width and the offset can go to 38 if I'm reading it correct. Is the 5.5 rim too narrow for the 205/50R15 tire? Thinking of autocrossing my '91 again after years away. Any advice for jumping back in to the fun?
Interestingly a set of 205/50R15 Nankang CR-S on 15x7's stack exactly the same height as 225/45R15 Hankook RS4's and both fit well on the 7" rims. Put a set of 225/45R15 CR-S on the 7" rims and they look pinched. Manufacturer declared tyre widths are an approximation!
Interestingly a set of 205/50R15 Nankang CR-S on 15x7's stack exactly the same height as 225/45R15 Hankook RS4's and both fit well on the 7" rims. Put a set of 225/45R15 CR-S on the 7" rims and they look pinched. Manufacturer declared tyre widths are an approximation!
Stacking mounted tires only shows section width...which varies according to wheel width. That's why those looked the same...both on narrow wheels.
What matters more for performance is actual measured tread width, which does not vary with wheel width.
That said, it is true that some tire models run wide, while others run true. Some of this is because of different carcass profiles (square shoulders versus rounded) but can also simply be a wider tire. The industry has a range of physical sizes that can be stamped with a given numerical designation.
2/23/24 3:49 p.m.
To run the NA in SCCA stock the 15" rim is limited to 5.5" width and the offset can go to 38 if I'm reading it correct. Is the 5.5 rim too narrow for the 205/50R15 tire? Thinking of autocrossing my '91 again after years away. Any advice for jumping back in to the fun?
2/23/24 4:02 p.m.
So I really like them on the stock 14" wheels. I think they are most fun on 185/60-14 tires.
7/13/24 3:11 a.m.
Interestingly a set of 205/50R15 Nankang CR-S on 15x7's stack exactly the same height as 225/45R15 Hankook RS4's and both fit well on the 7" rims. Put a set of 225/45R15 CR-S on the 7" rims and they look pinched. Manufacturer declared tyre widths are an approximation!
7/13/24 3:41 a.m.
Stacking mounted tires only shows section width...which varies according to wheel width. That's why those looked the same...both on narrow wheels.
What matters more for performance is actual measured tread width, which does not vary with wheel width.
That said, it is true that some tire models run wide, while others run true. Some of this is because of different carcass profiles (square shoulders versus rounded) but can also simply be a wider tire. The industry has a range of physical sizes that can be stamped with a given numerical designation.
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