Before you read the below, please note the situation I am bringing up does not involve "plus" or "minus sizing", as this is not a usual topic that is tabled! I'd like to bounce this idea off of folks and get an opinion here. Tire Size Calculator Pls enter these two numbers under the "tire comparison" tab. Size 1: 245 45 19 Size 2: 245 45 20 What I'm trying to figure out is (assuming tires used in both situations are the same tire, same load rating, same speed rating) 1) Which tire is noisier 2) Which tire is more comfortable. Let's look at a couple of interesting facts here between these two tires, one being 19" and one being 20" The width of both tires is 9.6" The sidewall width is both 4.3" So to me, it doesn't appear that one can make a blanket statement of saying "the 20" will ride harder", because, on the face of the math above, this is not true. My only thought here though, is which tire has more contact patch with the road? My immediate thought process is that a 1" wide tire (let's go to extremes), has a lot less in contact with the road than a 30" tire, so does that mean then that my two tire sizes above - the 20" has a lot more in contact with the road and thus would be noisier? My question above is based on the assumption that both cars are the same weight, which is impossible, but if we strip out all the variables, all things being equal, does a tire have more in contact with the road if it's a bigger tire?