Thanks for your comment!
I was pleased to see that that website offers pressure information about various tires, as I really wanted to know which tire could be inflated to 51 PSI. Unfortunately, they don't have the EcoContact 3
The EcoContact ESP on there doesn't come in 175/80/14 while the EcoContact 3 does come in 175/80/14 and I still don't know what pressure that tire can be inflated to. I do hope it can be inflated up to 51 PSI otherwise I'll not be too happy.
We don't have rain grooves - I've never seen those before. However highways do tend to get wear in the slow lane (rightmost lane for you) due to trucks, I think the same as the US, and wider tires are more likely to "tramline" in the wear grooves. I experienced this in my old Vauxhall Nova when I changed from 145/something/14 to 195/60/15. Sometimes the wear is severe enough to make 2 narrow shallow rivers which isn't much fun to drive through.
Anyway. Back on topic. Wouldn't increasing the width of the tire decrease fuel economy due to increased rolling resistance and increased frontal profile? Tires with a size of 185/80/14 are unusual, the selection is rather slim. I can't seen any fuel efficient tire with the 185/80/14 size. Oh well, this is probably why Vauxhall chose the 175/80/14 size when making the ECO4. I could go for an 185/80/15 size but this would require new rims which is easy enough to find, but I won't get a fuel efficient tire in this size and I think I'd be better off sticking with a fuel efficient tire in the 175/80/14 size.
Your thoughts?