maybe i underestimate physics or something but you must really be nailing those turns if that sound is tire screeching on pavement. have you tried different surfaces? ie the sound should be different if you are on a gray concrete sidewalk or black asphalt, in my neck of the woods there are a lot of neighborhoods where they started a huge construction project but then were halted due to the economy, so you have 16 blocks of cul de sacs and sidewalks and driveways and fields and new asphalt roads with no traffic whatsoever, a place like that would be good to try to compare turning sounds.
if you can find an area of hardpack dirt and it still makes that sound on that surface then it most definitely is not the tire. if the sound does not happen, or possibly at least if it is different on asphalt vs concrete then its possible it is the tire.