i am open to pinging....I have decarbonised the head, with a Jap fluid and with the can's the Subaru supply, changed plugs, put in high octane fuel...

reasons against pinging.....

1. no engine light
2. no real loss of performance ( expected from advanced engine timing )
3. no logs in the computer.....

I will have a look at the exhaust covers and see what's going on...

For the pinging, any other suggestions, things that I can try?

Cheers