So the car is an 88 5.7 tpi camaro, pretty much stock with 44,000 miles on it. Only things not stock are underdrive pulleys, afpr(47 psi), bosch platinum 4's, tpis wires, cap, rotor, msd coil, bosch 3 injectors 22 lbs, k&n, 52mm tb, 180 deg thermostat, fan switch, cold start injector delete, base level tpis chip(for cold start), new bosch maf, iac valve, tps sensor(.56 volts) and no vacum leaks. So that is the car Now the problem is after i set the timing, 6 deg with est wire dissconnected. The car now pings or knocks in upper rpms under load. why would factory timing specs cause ping or knock? I use 90 grade fuel as thats all thats in alaska acept race gas if you want more but it shouldnt matter cause the car is stock compression. When i bought it years ago and changed all the parts out the car had factory plugs still on pass side and split fires on driver side, which is why i believe that all internals are stock, as i am the second owner of this car and the man i bought it from said the only thing he did to it was plugs wires a shift kit( which was f'd up) and a superchip. so if all is stock why would 6 deg of advance cause a knock/ping?

 

Any one? just need an idea of where to look for further diag. i am just out of ideas any advice would be great. Thanks, Jason

 

Also forgot to add no ses lights or anything and i did set the timing by the tech article.