drivetrain problems?

So here the story, i just finished breaking in my new clutch which is a centerforce stage II. My first time on the freeway i am cruising in 4th at 2000rpm i go to pass someone and as soon as i get to 2500 rpm the car started to freak out. It seemed like either 4th gear is gone or somethings wrong with the clutch i just installed. The power would cut out then come back on. Prior to the install i had no problems with 4th. The car runs well throughout the rpm range in 1st-3rd. I thought maybe its the fuel pump starving the car since its probably never been replaced and i have 155000 miles on the car.

Thanks in advance,
Robert

O man thats a relief i feel much better knowing that this is either a problem with spark or fuel! when it cuts out the rpms drop a little then it just comes back on. i was thinking maybe replace the fuel pump and check the order of the plug wires and timing any other ideas?