1987 Chevy Camaro FI 350 (L98) driveability

I have a Camaro that I just rebuilt the motor for. I just got it back from a shop and it runs worse than the first start up. There is a nasty clicking noise coming from the right side under the valve covers. I adjusted all valves for #1 firing position, then the rest at #6 firing position (not running). I started the motor and the noise was still there. I checked the intake for vacuum leaks and found none. I then checked timing and it was good. I took the car around the block to see if it would go away, but found that trying to give it a little gas made it sputter, and I checked throttle linkage, throttle body, air cleaner, IAC motor, the works and found no problem. The only thing I haven't checked is the fuel system, but I don't think that explains the clicking. I have brand new injectors and MSD ignition, so I don't think a misfire is the problem. I do have a performance cam, but the springs I have said they can handle more than the lift I've got. I'm a pretty competent mechanic, but I'm out of answers. I've put too much time into this car to give up on it, any help would be appreciated