Track day - engine damage?

[SG4247]

These plugs are defective! Lol..

Went to the track Sunday with my 2010 touring WHTRICE.

Made a few laps and the car runs like gangbusters, and then just lays down on the last 1/8 of the 1/4 mile. Fresh bottle, proper pressure, etc...

Spraying 100 hp shot with the NX GTR dual plate kit with E85. I logged all the runs and was watching the AFR close. Same tune up went 11.58 and 11.62 three weeks ago.

On the first run, I did just bump the rev limiter on the 1-2 shift, but didnt notice any change in the sound of the engine afterwards. Car went 12.08.

Plugs in order as they were removed from the engine.

The “good” plugs came from the front of the engine cyls #1 and #2 as if you were standing at the front of the car. They get worse as you move toward the rear of the car.

Motor would start and run surprisingly. Still had to get a roll back for the trip home.

Not sure what happened, but cyl #5 has no compression. I mean zero.
The other cylinders are all 230 or more. I have bore scoped #5 several times and dont see a problem with the piston top. I figure its either smoked the rings or blown a head gasket...not sure yet. But even if it had collapsed the ring land I would expect some compression right?

Bummer...may need a short block.