Valve Float

I'm chasing what seems to be a valve float issue. Everything was bought together so it would be like a matching set. Spring pressures were checked & set up (from what the machine shop told me). When I first ran this engine combo, the wrong gear was in the car & turning about 8800. The valves were floating pretty bad halfway up the straightaway. I'm now turning right 7500 & it sounds like a slight float at the upper end of the straight. Could it be possible that I have weakened the springs turning it up so much? Thanks F-9

hydraulic or solid , makes a differance

Solid. 256/536

could be timing not advanced for that RPM

It's at 34

36 - 37 for 8800

advanceable cam gear? head shaved?

It does have an adjustable gear. Right now the cam is on zero. Was thinking about going 4 advance, but wanted to find the float issue before I did that. The head has been cut to the bottom of the intake studa