Yes, pretty much the same thing happened to my Z. I think the oil pump started to go bad, the engine had very few miles on it (it was barely a year old) and I didn't run it extremely hard. Anyway, I guess the engine wasn't getting sufficient oil or something b/c I checked the oil EVERY DAY and it always had the right amount of oil...never used any oil. Bastard spun a bearing...hell, now I think the bearing is just basically off of the rod. It still runs just fine...no detonation, no skipping...but it sounds like the rod is just being tossed around the crankshaft... We took it to a performance engine shop near here. It's possible that it only needs new bearings and maybe a new crankshaft...but they're going to break it open and see if a rebuild is necessary. If so, I might get them to port/polish the heads and maybe do a little bit of extra work while they have it apart. Have to get a price first, though... I only have a part-time job and I have to pay $100 per month on the car already... FUCK!