Is a 50/50 split possible as an MD/PhD?

I am a pre-med student recently graduated and am heavily considering applying MD/PhD. I have gone back and forth on this throughout undergrad because I LOVE both research and clinical. I know I can do research as an MD alone, but I like cell-based in the lab research opposed to strictly clinical, hence my draw to a PhD as well. My hinderance however is that I am mostly told to expect an 80/20 split research to clinical. I want to practice medicine more than that… Does anyone have some insight for me? Thank you in advance!