Z-Dad

OK, I searched a while for a thread discussing this issue, and couldn't find any...so here's what's happening.
My son got in the Z today after several days sitting in the garage, took it for a spin, and came home quickly saying something wasn't right. Said when he hit fourth gear at about 4000 rpm the engine kind of bogs or hesitates from increasing rpm's. I drove the car and noticed it as well. All other gears seamed to be fine, but definitely felt something in fourth.
The car does have test pipes, and this was the first day in the upper 70's and high humidity. We have been told that the clutch needs to be replaced soon, and not knowing much about clutches and motors, I don't know if that would be a cause for this or not.
Any thoughts?

Z-Dad

R350Zz33

iTrader: (4)

i have the same problem its the testpipes if im in 4th or 3rd and going to slow and go wot i can make it 2step lol