I can't even describe just what pinging/detonation sounds like, it's like a clattering sound when accelerating, not the same as the deeper clunk of something in the crank.
What was your engine temp when you got off the highway? How is your ignition timing setup, how much advance and are you using ported or manifold vacuum advance?
'84 Grand Wagoneer 360/727/229, 32" General ST's and 36" Swampers, 3" lift, TFI/Mallory 6AL, CS 144, Taurus fan, custom bumper, and custom 'bodywork'. Soon to have 6" lift
'79 Cherokee S 360/T15/D20, rusting away while I figure out what to do with it
'91 Final Edition GW in Spinnaker Blue!
My FSJ pics
FSJ Grille Identification