For drag racing, can I go with a smaller rim on the back with a bigger tire and keep my 19 on the front? - 1

Edit
2008 Ford Mustang

Right now i'm sitting at 245/45r19 fronts and rears 275/40r19

The reason for asking is because i can't find a drag radial or Slick that fits my rim?

Sure, I run 295-50-15 on the back. But if you start running slicks, watch your rear differential. Slicks can tear it up… Thank you so much! @rick

Thank you so much! @rick