I don't have much experience with detonation related signs, but I thought it would leave the piston top pitted. Sounds like you have more experience with this than I do. Are there any other marks or signs that I should be looking for?

 

That head gasket look pristine except at the fire ring on 6 and I am willing to bet it has been beating on that rod bearing.

It is a boosted car, that in itself is hard on head gaskets and under boost the margins for detonation are much smaller than with out boost.

As far as other indications of detonation, cracked Porcelain on the plugs, broken rings and lands, pitting or holes in pistons.

It running lean on that cylinder is what caused it to detonate in the cylinder IMHO.

 

Pics or calling your bluff.

 

Glad to hear you are getting it back together. I will have to stop by and see your project soon. I just got mine insured yesterday and took it out, felt good!

 

It’s alive!

Finally, after two and a half years, my 928 is running again. Last night, managed to button it up enough to get it running for a few seconds. For the next couple evenings and the weekend, it will be 100% finished so it’s drivable. Then have to get another set of tires, fill the coolant, change the oil and take it out for some shake down testing. I really hope that the oil separator will reduce the amount of oil that the catch can used to collect.

 

Glad your back together, I hope that you get the fuel system sorted so this wont happen again

 

Yup, took care of that too. Replaced all 8 injectors with Frod "blue top", 24lb units.