98 prelude losing power?

i have a 98 prelude 5 speed, with I/H/E. The past couple weeks I've been noticing a loss in power/acceleration 0-60 or 70. I used to be able to get the tires to "chirp" when i shifted into second and now it won't. Also now the car won't shift as fast...it takes a little while to actually get into gear. I just got the oil changed about 1k miles ago, and did fuel injector cleaner today. Still won't chirp and still slow. I've been noticing my clutch has been a little vague. Do you think that I need a new clutch? If so do you recommend that i install a light weight flywheel at the same time as the clutch? Any good brands for a performance clutch? Thanks!