Strange Heavy Load hesitation

[Topper]

After a HG change, car wouldn't start, got her running (CAS was out), adjusted/corrected timing, Car now idles fine and will rev slowly/smoothly with no issue, small blips up to 3k are fine, but if opening the throttle harder/fast (only tried when stationary) the car almost cuts out before recovering and revving.

Have checked timing and adjusted the idle to 820-850, any thoughts/suggestions?

Everything appears/looks fine - confused

 

[Nicely]

Check there's no loose earths which vibration could be causing loss of contact.

 

[Topper]

Strange you mention that as a dodgy negative terminal on my battery has been a right pain recently........ Best get a new battery!

Presume Datascans data display would show show this us if I try it as it reads battery output.