That is a loaded question. The whole front vs rear tire size thing and handling balance will depend on a number of factors such as weight distribution and chassis setup. I just downgraded my budget a bit on my car and have decided the cheapest way to get what I want is with the Trans Am GTA wheels. They look like what I have, but have a staggered offset. On a stock G body, this is a no-no, but with the tall spindle conversion you need more offset up front than in back. Since this is in my plans, I can actually use a whole set. As an added bonus, there is a slight chance of finding a used set for cheaper than one 17x8 in wheel I would want. Sure, they are only 16x8's, but it is a size that I think still looks good on a G body without breaking the bank. As an added bonus, they are not really cool to a huge number of people, so there is less chance of getting my car stolen for them. Since the Cutlass may become my only car by the end of summer, this is important. All I need to do now is scour Craigslist and the junkyards in hopes of finding a complete set that isn't bent.
My planned tire sizes? 245 50 16 front, 255 50 16 rear.