[Sfvalley135i]

Heres my valves at 40k miles!!

[Brian_VACsales]

Reputable independent BMW shops do the job for $400-500 in a day - seems like a good, no drama deal to me.

Doing it without the adapter is a PITA and not all equipment is created equal. The combination of walnut shells and proper suction make the job 'proper' in my educated opinion. Forget the spray a chemical and scrub method, generally speaking NO ONE does that.

Originally Posted by mweisdorfer

There are plenty of DIY's on walnut blasting. It does not look that difficult to do. You just need the gun, very fine walnut shells, an air compressor of at least 6 gallons and the intake valve adapter.

This is assuming you have a decency set of tools to begin with.