WHEN I BOUGHT THE CAR 9/00 IT WAS IN STORAGE FOR 13 YEARS WITH ONLY 13K MILES. THE VALVE SEALS WERE SHOT SO I CHANGED THEM AND INSTALLED 1.6 SUMMIT ROLLER ROCKERS AND SET VALVE LASH PROPERLY. NOW AT 5000RPM THE VALVES FLOAT OR SOMETHING LIKE THAT. GOT ANY SUGGESTIONS? I CALLED GM TO SEE IF THE SPRINGS ARE THE SAME IN AN 86 IROC AND SS AND WAS TOLD THEY WERE. MY SS WILL PULL TO 6000RPM BEFORE ANYTHING HAPPENS.

 

valvesprings go bad from sitting installed on the engine but unused.

 

What he said!