Ill get ypur head off tomorrow jon c what has gone wrong (off your car i mean)!
I will also cheak head c if its like a nana!
Any one one here know what the max is for skimming ?
I was told once aslong as the surface is no lower than the end of the exhanst stud?
That sounds a bit of a rough guide to i would rather cheak it properly.

If to much is skimmed off is there a chance of valves toutching pistons?

Suppose thats a daft question it has Big valve cut outs in pistons