I am betting a plug was bent over and he bent it back and regapped them. That is my theory.
Basically here is the deal slick. Something is wrong with your car whatever it may be. When my motor blew it was a random misfire and I checked the plugs and one of them was not gapped correctly either. IT WAS BENT. I chipped a piston. Let me tell you I had: Intake, T-Stat, plugs/wires, 1.84RR, 3" Downpipe, 3" Custom Exhaust Straight-Piped, DHP PCM and a 3.4" Pulley and it still blew up. I think your problem is you do not understand you have to take in account for dropping the pulley size. I don't think a 3.5" is safe for a stock car; I don't. You're dropping .3" in pulley size...get some supporting mods. I dropped to a 3.5" with a intake and u-bend delete...I think that is what killed my motor to begin with. These cars are iffy and you have to be sure you have supporting mods to drop a pulley and whoever says a 3.5" is safe on a stock car is retarded. We keep explaining these things and it seems like no one listens...why do I bother
