Classic Audi Community General Chat » New tyres for my Audi 80 Cabriolet

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Old 24-06-19, 03:08 PM   #1
edwardbear
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Default New tyres for my Audi 80 Cabriolet

I'm using the standard 15" wheels but would prefer a lower profile tyre. What are my options?
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Old 25-06-19, 11:17 AM   #2
quattrodave
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16 inch use a 205/55 tyre or if you want wider width/lower profile use a 225/50
17 inch use a 205/50 or if you want wider width/even lower profile use a 225/45

Any of the above would keep the overall diameter similar to the original 205/60 x 15 or 195/65 x 15 depending on what you have fitted now.

Would need 7j rims idealy and the later cabs came with a 4 x 108 PCD wheel in either 16 inch (8 spoke can't remember the name) or 17 inch (bolero + rare and expensive) assuming you want original audi wheels.

You could go 18 but then its aftermarket wheels only and the tyres would need to be 205/45 or 225/40 but the the ride quality would be crap (in my opinion) as you've only got 90mm ish (3.5 inch) of rubber between you and the road compared to 122.5 mm ish (nearly 5 inch) on standard tyres on 15 inch wheels.
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Old 25-06-19, 11:21 AM   #3
edwardbear
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Originally Posted by quattrodave View Post
16 inch use a 205/55 tyre or if you want wider width/lower profile use a 225/50
17 inch use a 205/50 or if you want wider width/even lower profile use a 225/45

Any of the above would keep the overall diameter similar to the original 205/60 x 15 or 195/65 x 15 depending on what you have fitted now.

Would need 7j rims idealy and the later cabs came with a 4 x 108 PCD wheel in either 16 inch (8 spoke can't remember the name) or 17 inch (bolero + rare and expensive) assuming you want original audi wheels.

You could go 18 but then its aftermarket wheels only and the tyres would need to be 205/45 or 225/40 but the the ride quality would be crap (in my opinion) as you've only got 90mm ish (3.5 inch) of rubber between you and the road compared to 122.5 mm ish (nearly 5 inch) on standard tyres on 15 inch wheels.
I'm still using the current 15" wheels so would need to know what tyres would fit the 15's and still achieve a lower profile.
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Old 25-06-19, 06:23 PM   #4
Duffy3074
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https://tiresize.com/tyre-size-calculator/

This is useful as a comparison tool
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Old 25-06-19, 07:40 PM   #5
audi80fan
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Originally Posted by edwardbear View Post
I'm still using the current 15" wheels so would need to know what tyres would fit the 15's and still achieve a lower profile.
Would that look a bit strange? Like the wheels are too small?
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Old 25-06-19, 08:27 PM   #6
quattrodave
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Originally Posted by edwardbear View Post
I'm still using the current 15" wheels so would need to know what tyres would fit the 15's and still achieve a lower profile.
Thats not possible cos if you fitted lower profile tires to the 15 inch wheels the rolling radius would be reduced so the car would be over revving in all gears and top speed would be reduced or you'd blow up the engine due to the excessive revs.
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Old 25-06-19, 09:27 PM   #7
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You'd need to go to 225/55 15 .

Not something I'd recommend on a standard rim
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Last edited by mikes2; 25-06-19 at 09:31 PM.
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Old 26-06-19, 03:37 PM   #8
edwardbear
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Originally Posted by quattrodave View Post
Thats not possible cos if you fitted lower profile tires to the 15 inch wheels the rolling radius would be reduced so the car would be over revving in all gears and top speed would be reduced or you'd blow up the engine due to the excessive revs.
I'm currently looking at 195/45 15. In terms of the profile of the tyre I'd be happy with that.
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Old 26-06-19, 04:19 PM   #9
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That would look so wrong. your speedometer reading would be way off. that would give a tyre difference of more than 10%
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Old 26-06-19, 08:25 PM   #10
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Quote:
Originally Posted by edwardbear View Post
I'm currently looking at 195/45 15. In terms of the profile of the tyre I'd be happy with that.
WOT


Tyre height drops nearly 3 inches (75mm in metric 24.7 inches down to 21.9 inches) so big gap between wing wheel arch and tyre edge, you would lose 1.5 inch in ground clearance (35mm metric) , speedo readings go out by over 11% so at 70mph on speedo actually doing 62 assuming its accurate now and in my opinion it will look really stupid.
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