Got some shorties for my 97z. Will shorties move the torque up in the powerband on a stock car or will it stay the same and just improve?

I know mids and LT's move the torque curve up in the powerband but I don't know if shorties do this as well? (stock cat & exhaust).

 

From all the dyno graphs I've seen, shorties will give you more torque all across the rpm range, but tends to show more improvement in upper rpms. Long tubes also give more torque across the whole rpm range, but also boost the torque in the lower rpms as well as the upper.