Matt Harvey can bring the heat, but is starting to gain pride in his ice. “The biggest thing last year was not having my curveball,” the Mets right-hander said yesterday after allowing two runs over 5 1/3 innings in the Mets’ 3-2 win over the Cardinals. “I threw a lot of good ones [yesterday] and was able to throw it in the dirt when I needed to. That’s a big pitch for me, so having that back is definitely a big plus for me.” In five appearances this spring, Harvey has posted a 2.95 ERA, with 24 strikeouts in 18 1/3 innings. He is scheduled to make two more spring training starts before getting the ball against the Padres on April 3 for the Mets’ second game of the season. Jon Niese is expected to pitch Opening Day, followed by Harvey, but manager Terry Collins still hasn’t officially announced his rotation plans. “This is the longest I’ve gone this spring and even to the last pitch I was feeling good, so that is definitely a plus,” Harvey said. “I’m showing that the offseason workout is paying off and my arm feels great. Pretty much I’m ready to go. I am liking the way everything feels.”