jimboslice

Looks like a picture of the top of the piston via bore-scope. Green tinge along the edge of the walls indicates pooling coolant.

Do you have a bunch of white smoke coming out of your exhaust, even after condensation inside the piping burns off? What does the coolant in your radiator look like?

mrlegoman

Top of piston #3 with a bore scope.
Did a pressure test this morning on #1 and #3, got bubbles coming out of the radiator.....

mrlegoman

Not really. Initial start up puff, but nothing after that. Coolant color looks normal.

jimboslice

It sounds more to me like a headgasket leak rather than a straight up failure.

The engine was put together very recently, miles-wise. I would think it possible the PO didn't torque the head studs properly, thus causing the leak.

I would just take it in to a shop you trust and get it looked at. Or, you pull the head and see it for yourself.

Here's a thread I found in which the OP is describing somewhat similar symptoms:

https://www.s2ki.com/forums/s2000-un...aking-1178371/

Good luck!