New Zealand recovered from 86 for four to go to stumps on 361 for five.
After being asked to bat first New Zealand lost both openers in the first seven overs and four wickets in the first session against the Irish, who were playing just their 13th test.
Tom Latham made a two-ball duck, Devon Conway scored four, Kane Williamson 36 and when Daryl Mitchell was dismissed for one, New Zealand were teetering on 86 for four.
However, Ravindra and Blundell put on a 217-run partnership for the fifth wicket.
Ravindra scored his fifth test century, eventually dismissed for 121.
Blundell made his highest test score and was unbeaten on 142 at stumps with debutant Dean Foxcroft on 38.
It was Blundell's sixth test century.
In a sideline interview after play Ravindra said they had a lot of work to do on the first day.
"Ireland bowled really well, put some pressure on us, bowled in some great areas and really made use of the surface and the nip that was in it.
"We recognised how well they were bowling and obviously had to give ourselves time and play the right way with that Duke ball swinging around and luckily enough we were able to score at the back end."
Ireland pace bowler Mark Adair took three wickets.
New Zealand included Foxcroft in their XI along with a pace attack of Nathan Smith, Zak Foulkes, Blair Tickner and Ben Sears.
The four-day test against Ireland is followed by three tests against England.
