pinging under load with K-jet

Hi Guys
I have a new build 2.0 DX block, running K-Jet, problem existed before the upgrade to 2.0 and since startup on the new build I cannot get rid of a ping under load with the k-jet, spark plugs are new, timing is ok as well.
What can I do to rid the car of pre ignition, it seems the k-jet is running too lean, hope you can point me in the right direction. The car will be tuned in a couple of weeks time, but it is bothering me a bit.

Thanks

You certainly don't want to continue running with it like that ! Try running on super unleaded until you tune it properly, failing that look out for an old K-Star unit and fit that.