By Bruce Mohl

The sparks are about to start flying between developer Don Chiofaro and Boston Mayor Thomas Menino.

Chiofaro wants to build a pair of 625-foot towers on the site of the Harbor Garage along the Rose Fitzgerald Kennedy Greenway, but recently released city zoning guidelines for that area allow building heights of only about 200 feet. Chiofaro scheduled a press conference for Wednesday where he says he plans to present evidence that the process used by the city to develop its guidelines was “compromised and flawed.”

Chiofaro called me with a personal invitation to the press conference. “We’re cranking it up to another level,” he said.

Menino and Chiofaro have never gotten along, perhaps because they’re too much alike. But until now the developer has largely refrained from challenging Menino in public. Instead, he’s made his case behind the scenes.

For example, Chiofaro last year was handing out business cards that made the economic case for his towers. On one side of the business card was a picture of the Harbor Garage under the headline “an eyesore.” The business card noted the garage paid annual taxes of $2 million to the city and employed 50 people. On the other side of the card was a question mark next to the garage under the headline: “Tomorrow: An Icon.” The proposed Chiofaro towers at that time, according to the business card, were forecasted to pay the city $16 million in taxes and $10 million in linkage payments and lead to 4,720 permanent jobs.

Menino has never hidden his dislike for Chiofaro. In an interview before his election to a fifth term last year, Menino told CommonWealth that Chiofaro was going through the same development process that every other developer goes through. But then a few moments later he acted as if that process was irrelevant, saying Chiofaro’s buildings would never get built as originally planned, casting shadows over the Greenway.

“He’s not God. He can’t buy the process,” Menino said of Chiofaro. “It’s not my responsibility to make a developer a gazillionaire. No. This is my responsibility. I have a responsibility to the taxpayers of Boston to try to develop the city, and one of the things I think we’ve done is continue the European look of Boston better than most cities. That’s important. We have progress, but controlled progress.”