fine. flow will be _slightly_ decreased over a larger bore due to slightly more shrouding. would be more pronounced the bigger the valve (say, a 2.08 over a mag sized 1.92 or 2.02)

IMHO the only reason to do a 318 stroker is to use a pretty common '85-91 318 roller cam block, and use a hydraulic roller cam and stock roller lifters. otherwise, you're just giving up 18-34 cubes.