From what I’ve seen, a lot of admitted Pratt students do have 36 Act and at least 2 near 800 STEM SAT 2 scores. You can submit your ACT, but I would recommend retaking your subject tests to remain competitive. Obviously your grades in your math and science classes will matter just as much. Also, since you won’t get to calculus till your senior year, there is a high chance of you getting deferred in the ED round so the AOs can see your grades in your first semester of calculus (most Pratt applicants take calc during sophomore/junior year).
Or, you can apply to Trinity (Arts and Sciences College) instead, which does not place as much emphasis on STEM subject test scores than Pratt does, and transfer to Pratt later. Many students transfer between the 2 colleges, some even back and forth. Good luck.