A carbon shaft with the same spine would be Carbon Express Heritage 90,it is very close to .540 spine.But it is hard to compare spines between aluminum and carbon and expect to get similar results.They may be close but react differently,they need to be tuned to your bow.A Heritage 90 is 9/32" diameter and a 2113 is 21/64" diameter,thats a difference that will affect tuning also.You should be able to tune carbons to your bow,plus a carbon is alot tougher of an arrow then an aluminum one especially one with a .013 wall thicknes.