So I picked up what i thought was a stock swap from a buddy of mine. I popped off the valve cover to find Omni power springs and retainers along with CTR cams. So i decided to pull the head. I was wondering what kind of valves these are. On the exhaust valves there are F's in the middle.

Thanks for the help!

 

Stock ITR valves

 

Thank you and can anyone verify that?

 

I'm looking at a 97 p73 cylinder head so I am sure.
I am not sure if a pr3 b16 head uses the same valves. I don't have one to look at right now!