detonation
 

car is a 1994 mustang GT 5.0, bone stock, 94k well taken care of, 87 octane.



Runs just fine except under WOT it pings pretty bad. Pulled plugs for a tune up and they were white. Replaced plugs, wires, cap, rotor, fuel filter, and changed the oil (needed a tune up real bad). It still pings, but feels like its running stronger. The car hasn't been tinkered with at all, so it probably isn't the timing. Any ideas on where to look on this? The car is bone stock I don't get why it would ping...

I'd double check your timing first with a good timing light and spout disconnected. If I've learned one thing working on cars, its NEVER assume anything. And ALWAYS double check!

ok, i'll check that. Any other ideas?

O2 sensor?
 

Could be the O2 sensor, especially if it's never been changed.

Rev

02's don't alter A/F at WOT, which is when it pings.

Have you tried any higher octane gas?