very very very bad times. I have a 92 gsr with intake and exhaust and I ran it down the trake 4 months ago and I could only get high 16's out of her. Some people said I had a clogged cat. I had it checked it was fine. My shifts were fine, the only other thing I can think of is the engine is exhausted

 

You are shifting at REDLINE right?

Check your timing and plugs too. Good luck!