My Superb 170 TDi CR Elegance Hatch comes with 18" wheels and 225/40/18 low-profile tyres as standard, but for the winter I fitted a set of 16" after-market alloys with 205/55/16 winter tyres. They fit perfectly and the car rides better, is more tolerant of bad road surfaces. It also returns a 10% improvement in fuel consumption. Low profile tyres are clearly unsuitable for our notoriously pitted roads, and I suspect they are fitted more for fashion/cosmetic reasons than for practicality. "Honest John" in the Daily Telegraph makes this point repeatedly. I now intend to fit summer tyres of the same size to these alternative wheels. 16" wheels are standard on some "lesser" Superb models, so is there any reason why I shouldn't follow this course?

Provided your insurers are happy with it , no reason at all

How many miles have the 18"s on your car done? and where in the UK are you? I have a feeling you could get some offers to swap for 17" wheels real soon ....if you where close and had unmarked wheels with about 3,000 miles I'd be tempted

Not only will you get better economy, but you'll can do better emergency stops (and get better acceleration too if that matters).

Yes its a well known performance modification to fit skinny high profile tyres :)

Cars in the 1970's were so much better than today

Not only will you get better economy, but you'll can do better emergency stops (and get better acceleration too if that matters).

How will it stop better?

With more tyre and less wheel, the ride will be marginally improved but the handling will be worse. - braking / acceleration in the dry, should be worse with less contact to the ground. - surely?

Al.

Not only will you get better economy, but you'll can do better emergency stops (and get better acceleration too if that matters).

How come? Wheel diameter is still the same, roughly (less than 1.5% difference).

My Superb 170 TDi CR Elegance Hatch comes with 18" wheels and 225/40/18 low-profile tyres as standard, but for the winter I fitted a set of 16" after-market alloys with 205/55/16 winter tyres. They fit perfectly and the car rides better, is more tolerant of bad road surfaces. It also returns a 10% improvement in fuel consumption. Low profile tyres are clearly unsuitable for our notoriously pitted roads, and I suspect they are fitted more for fashion/cosmetic reasons than for practicality.

I couldn't agree with your more. I feel sorry for you guys in the UK, who are forced to have these expensive and uncomfortable 18" wheels when you simply want a comfortable and luxury car (and therefore an Elegance).

Personally: I bought an Elegance in Europe, and sold my new 17" wheels. With the money I got I could easily buy a set of 16" wheels in a design and rim width I liked best.

Now I have the car just as I want it: Luxurious, comfortable, with reasonable fuel costs and low maintenance cost. The 205/55R16 tires are common and cheap, moreover, my 6.5x16 rims can handle large potholes without incident and won't be damaged when parking (too) near to curbs.

Regarding fuel consumption: I have about 10% higher fuel consumption with my Michelin Alpin A4 tires compared to my Michelin Energy Saver summer tires. This is due to the Alpin's higher rolling resistance, the lower temperatures in winter (higher air resistance) and the longer time it takes for the engine to warm up.

But if you have 10% lower fuel consumption in winter, this means that if you change your current 18" wheels to a more sensible 16", you could fuel saving could be up to 15%, especially if you buy the energy efficient Michelin Energy Saver tires. (Make sure you get their brand new, further optimized series, Michelin Energy Saver +).