Baking a cheesecake at 325 instead of 350

I have a cheesecake recipe that I have used for years, It is as close to perfect as I need it to be...except, sometimes it cracks (maybe 1 of 5). I have never used a water bath and I don't want to start. I was thinking if I lower the temperature from 350 to 325, it might stop occasional cracking. If I bake for 41 minutes at 350, how much time should I add if I bake at 325? It has also been suggested that I add a tablespoon of cornstarch to the recipe...any thoughts on cornstarch. Thanks