Doesn't it depend on the width of the alloy also.... it does not matter if they are 19 or not, but rather:
Are they 7.5, 8 or 8.5" wide... that is what you should be looking at and then matching the tyre to that.
I have 19 x 8 with 225/35/19 front (to clear coilovers) and 235/35/19 back, not had a problem with either ' fallling off'. Would never drop it to 215 though I don't think - the ride would be unbearable.
Are they 7.5, 8 or 8.5" wide... that is what you should be looking at and then matching the tyre to that.
I have 19 x 8 with 225/35/19 front (to clear coilovers) and 235/35/19 back, not had a problem with either ' fallling off'. Would never drop it to 215 though I don't think - the ride would be unbearable.

