bigger rims won't do you any good except cost money. yes a larger diamater tire will assist in handeling, but why not just a thicker sidewall tire to make the tall tire, bear in mind that this could throw off your speedo a lot and it will change your rear gear final drive ratio also if it is a lot taller. The problem with your Nova is it has a BB in it and stock front everything which would have been designed for use with a small block which is much lighter, b4 assuming a larger tire will do better, change to heavier springs, add a sway bar and polyurathane bushings to the front end.