This is something that has been known about for some time but I cannot think I have seen anything on here before. Something to check if you get to remove your M3W X-Wedge cylinder head. They have been known to crack between the valves, as this one has in the photo. No signs of it before the head was removed, it all ran perfectly. This particular engine had only done 16,000 miles and both heads had cracks. The crack extended into the exhaust valve seat. Unless you have a reason to remove the head you will probably never know, ignorance is bliss! I am old that there have been some cases of the valve seat coming out....not ideal!

If you find the head cracked then Phil Bleazey certainly has exchange heads that have been repaired and upgraded with new seat inserts. They come in a vapour blasted finish, so will require polishing, if you have a polished engine. I expect that M3W Services also have a similar scheme.


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