when i'm on the highway and I get into the throttle it responds well for awhile put it starts to act hesitant after I take it to higher rpms? I'm on the pedal but its like backfiring a couple of times and hesitated very noticiably. Is this valve float? or any suggestions.

 

sounds like it. How many miles are on the springs and at what rpm are you noticing the back fire.

 

the springs probably have about 20,000 miles or so. I'm noticing this after I get into the 5000 range.

 

This is a back fire correct? Not just a miss at high rpm. I would think its valve springs, but maybe someone else can help more. Although 20,000 miles doesn't sound like much, if its 20k track miles it might as well be 80k street miles. You might want to pull a couple of springs off and take them to a shop to have them tested.