Not sure I mentioned this yet, but last time at Sebring my motor let go, no bang, just an immediate loss of power and a LOT of smoke, I got off the track OK and the weekend was over. Upon initial look, no oil leaks, no hole in block, it looked like a catastrophic head gasket failure with oil in the radiator and spewed around the motor compartment.
I removed the motor yesterday and WOW, in the intake tube and airbox were small chunks of aluminum and part of a piston ring! These parts made it backwards through the manifold (and butterflies), through the MAF, and into the intake tube (with lots of oily radiator fluid).
Cylinders 1 and 2 are holding water in the intake tracts, cyl 3 has aluminum chunks in the intake track, and cyl 4 has 1 intake valve to piston contact and missing 1 head.
Short of physical damage from the metal parts coming back through, would the MAF and other parts be OK to use considering being exposed to the oil/water mix?
Not sure of the cause at this time but will be installing a spare motor. Perhaps this weekend I'll tear the motor down and see the rest of the damage.
Thoughts on cause. I know hard to say w/o seeing but I am leaning toward overheating or a lean cylinder, maybe injector issue. Any clues to look for?