There are plenty of dyno charts showing 22hp gains from the pacesetters I have dynatechs on mine and they made a nice improvement. Jim take a look at your shorties then stock manifolds then lts you will see the difference and I promise you get some lts you will feel the difference no comparison. The only time I would think about shorties is if I had a radix where it will help with torque but even then I would rather have the hp gain from the lts since a radix makes such nice torque down low anyway.