28 on ACT vs. 1400 on SAT

Should I retake the ACT if I got a 28 but got 1400 on the SAT?

Most concordance tables show that a 1400 is around a 30 on the ACT; if you took the SAT after your ACT, I think it shows your improvement in test taking. However, I think you should probably just improve or submit your stronger test and forget about the other one. I got a 29 on the ACT, but a 1480 on the SAT, so the SAT is clearly better formatted for me. The choice is yours, but good luck with whatever you choose!