Wider will increase the road friction so rob a little power. Larger diameter will rob a little engine power also and be the bigger contributor towards this. I have no idea how that will affect the apparent feel of the vehicle or sluggishness. It will be most noticeable if you have a 1.6ltr engine and probably hardly noticeable if a 3.2ltr. Others can comment better on this. I have a 3.2ltr and although my tires and slightly larger I didn't notice much change. It will also affect the speedo but in my case the increase was less than yours and I consider that it probably zeroes out the tendency to under-read that is inherent in most vehicles. In your case you need to be aware of this if you happen to have over zealous cops around.