CHEVROLET CAMARO CYLINDER HEAD VALVE SPRING

I Think I Have A Valve Spring Getting Lose In My 96 Z28 Can I Fix It Without Droping The Motor Or Can I Just Take The Covers Off And Tighten...

Have A 87 Camaro With A 383 Stroker Motor In It. Runs Really Good Up To About 5000-5500rpm Then Seems Like It Hits A Rev Limiter And Runs...