Well Im rebuilding the stang this month with a 331 CHP stroker with AFR 185's and a trickflow stage 2 cam, my question is for about 2 1/2 years my engine ground strap has been attached to the bolt on the back of the ALUMINUM A/C line that connects to the A/C compressor and to the stock location on the frame rail, well it has always pinged under load even after every fix i've tried...replaced all sensors and such, and my voltage guage spikes up and down...would that bad ground cause these problems??? maybe even ignition problems??? Needless to say i will be istalling the engine ground back during the engine install.