Piston deposits?

[Rikki Kitto]

OK any of you engine gurus out there have an opinion on my old engine. Just wondered if anything could be assumed from the deposits on the tops of the pistons, the plugs looked pretty oily too

[audi.e2.quattro]

it could be a sign of worn piston rings ? have you hade the engine pressure tested before you took it apart?

[pasbogdan]

Oil deposits should not be a problem anymore(you will get another engine).The problem should be those gold color marks on each piston.And if it was ping you will get it in any engine you will put and will not last.But someone more experienced should meke light in this case.
Each engine mechanical failure occurs needs special atention.If not 2 or 3 engines will get changed.

[JP]

When you get clean flash marks like that it happens because in that part of the combustion there is no fuel being burned. This generally comes from fuel and air not mixing properly before the combustion process.
If running stock heads and pistons the only thing that would cause that is poor injector spray pattern through age and contaminents.

[Rikki Kitto]

it could be a sign of worn piston rings ? have you hade the engine pressure tested before you took it apart?

No is the short answer but didn't seem to be a compression issue

[Rikki Kitto]

When you get clean flash marks like that it happens because in that part of the combustion there is no fuel being burned. This generally comes from fuel and air not mixing properly before the combustion process.
If running stock heads and pistons the only thing that would cause that is poor injector spray pattern through age and contaminents.

Maybe worth getting the injectors cleaned too then