But overall I would not be afraid of a 275/55/19 tire, the sidewall is still relatively small compared to a 33" tire on a 16" wheel.
I appreciate the post of all that useful data. However, my own experience on different tire shapes says 275/55 will actually be noticeable and I would think it sucks on how it feels. The sidewall is plenty tall enough to make a difference too.
I told you above, on a lighter car I could feel the difference, surprisingly to me, between a 255/40-18 which truly sucked, horrible, and the stock 245/40. Now, it was 2 different brand tires, but you could actually see the shape tapered into the rim lip from the tread outer edge. This was on an 8" wheel. You could feel the whole car make an initial weight shift starting into a corner. Now, on a boring vehicle or taking it super slow, you probably would never notice until you had to avoid a deer then the thing would actually contribute to over-steer because most people do some anyway when surprised.
This "lurch" of the weight, then back when you try to correct, is not my idea of a good handling tire spec.
On the very same wheel I then went to a 245/45x18 and it was night n day. Of course the psi were double checked, and various scenarios were tested mimicking panic avoidance and hard cornering approaches. These were easy to feel due to the tight handling of the bmw suspension and chassis.
Then I put that size tire, 245/45x18 onto an 8.5x18 and the tightness was even sharper. Perfect really. The shape was not like a "stretched" tire but it did have a perfect gentle angle from tread edge to rim lip.
Since then I put on new winters on the 8" wheel, 245/45 again but in Nokian and even RFT but they are constructed a bit wide at the tread o they still have an inverse shape a little.
Overall, the tire brand and model will likely matter in this idea but I am sure there is no 275/55x19 that will be doing it's very best performance on an 8" wheel. 9-9.5" sure, would be perfect.