Changing 8 fps animation to 24 fps but having the same timing


I started an animation in 8 fps thinking I could just triple the frame exposure rate later at ease to work with 24 fps. I want all the frames to have the same amount of screen time except when you switch to 24 fps, the frame exposure stays the same. How could I change the entire projects frames to have triple the frames to make that work? I’ve done a lot of work on this animation. I was trying to basically storyboard my animation before I actually made it smooth and polished with in betweens but the 8 fps is not something that would work for my animation as it is a fight scene with lots of really fast movement. Thank you in advance if anyone comes up with a solution. I searched all over the web to find a solution but there doesn’t seem to be one. TTRockStars