pinging on an hill?

I was coming up a hill today and put the pedal to the floor at around 35mph. It kicked down a gear and took off. My problem is it started pinging pretty bad. I am running 12* advanced initial and 35* total with no vac advance. I am running a holley 670 avenger out of the box. 360 10:1 compression, lunati cam with 1.6 clearwater magnum heads. lift is about 490 duration is pretty mild just a street cam. I did notice that my plugs are VERY clean. I can't tell if I'm lean because there is nothing at all on the plugs. Should I try going up two jet sizes at a time on the primary and secondaries?