Same person...
Huh?
Hope you weren't running Skunk2 or Supertech valves?
Damn Ian, that's some damage man.... those retainers have completely failed on you.
Is the spring in two ?? It looks like the retainer to me.
What a mess, at least you made the right decision in buying the m3.
Valve failure can be quiet often traced back to worn valve guides, are yee lads checking guides before build? Most heads I've seen recently need all new guides
Why would that cause it? No fuel for cooling?
Yeah lean mixture if it's not working fully. Will see in time.
Only one cylinder is like that so can't just be the heat/pressure of the turbo setup, you'd expect the other cylinders to look similar.
Why would that cause it? No fuel for cooling?
detonation? faulty injector?
ijwhiteman, sorry to see and read this...
So what are your plans now?
No signs of Det on the pistons/plugs. This is what I immediately thought, I used the local 98 octane fuel and thought it had started to Det, but there are no signs of that anywhere. Clearly something caused it to get hot, you can see the marks on the cylinder walls from the expansion. No doubt he piston skirts will be scored up aswell once I get them out.
Obviously I'd like to get to the bottom of what happened so it doesn't happen to the next engine that goes in.
Move on
I have bought a BMW M3.....
Surprised your not using the 102 octane....
Move on
I have bought a BMW M3.....
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