I am helping my son fix an '85 Camaro for a daily driver. We would like to know if the stock z/28 rims and tires from a '93 would fit his. The bolt pattern of course would be the same does the '93 have the same back spacing as an '85?

No you'll need spacers. These type of spacers aren't the cheap $20 per pair type. They'll be close to 2" thick I believe and go for $300-$350 a set.

Jody