There are some very interesting wrinkles to this question. The original production of WEST SIDE STORY closed in June 1959, then went to play on the West Coast, then returned to Broadway in April 1960, so it's highly debatable as to whether or not that should be considered a revival.
Also, among the Broadway productions of WSS and PORGY listed by ibdb, one of each show was at City Center, so that makes things very neat for comparison purposes. But there were other major NYC productions of both shows, including WSS having been presented at the New York State Theater as part of the Music Theater of Lincoln Center series, a production that is NOT listed on ibdb; and PORGY AND BESS at Radio City Music Hall in 1983, which IS listed on ibdb.
Bearing all of that in mind, I would say that P&B would still have to be considered the winner by any "Broadway" standard.