does a dead spot feel like if the car losses power/hesitates?

I think i have finally found my problem and its a dead spot and not a different problem. when driving around 50-60mph it seems like hte car losses power until it gets to 60,

if you drive the car at WOT or more throttle than just cruising you don't feel it.
also doesn't happen in 3rd etc.

so is this a dead spot? car has hughes 3200 stall, 3.23 gears.