I've only read the first volume of the manga, and I've watched the anime series.
It is quite common for an Anime and Manga to have completely different story lines (Two prime examples are Neon Genesis Evangelion and His And Hers Circumstances, both have reasonably different story lines, and one of them goes way beyond the other in the story line department [H&H Circumstances]). This is primarily due to the limitations of film media. You only have so much time to tell a story, naturally, things will changed. This simply just isn't so for print media.
As far as I know, there hasn't been any plans for a second season to Suzuka, which is kind of a shame, because there's so much more story to go on. Considering that its been two years since the anime finished its run in Japan, don't get your hopes up.