OK To make a long story short, the car was working fine no probs no noise.

New CAM installed, nothing special just mid range power, but now when the car is started it's a little harder to start and doesnt like sitting below 1500 rpm, it's like it wants to stall when its sitting below 500rpm and the rockers are making heaps of noise up to 1500 rpm.

Anyone got any ideas?

Is it a regrind and need extra shims?

Might have excessive clearances which could be causing the rocker gear noise. Like what MadMatt is referring to, if it's a regrind it will need to be shimmed according to how much was ground off the cam.

The idling issues could be the ECU relearning things. Mine went through similar symptoms on the first few starts after a cam change.

All working good now, cam gear wasn't tight the loctite didn't take so got some new stuff on and working like a trooper