I believe 400-440 cca. Next time try and turn the key to the on position for 3-5 sec then start it. But regardless, the first week I had my car I put a 700 cca battery in. Subaru always puts small batteries in for some reason. If recommend a durralast gold or something from advanced auto parts with more like 500-700 cca. I had a couple rough starts with mine the first week, like people are commenting on. After the new battery I've never had a slow start