930 valve guides 2013

[William930t]

In another relevant thread there is a discussion on engine rebuilds vs. length of ownership. It got me thinking about cylinder head rebuilds, specifically 3.3L exhaust valves and guides. Before I call Bill, what is the latest thinking on getting longer top end service life on our hot high output engines? There was a 2005 discussion on sodium vs. stainless valves, as well as ferrera vs manley vs iconel, anything new? Is it still advised to use copper for seats and bronze guides?

[full quack]

Uhmmm..... sodium valves are stainless steel, they are simply made with a hollow stems that is sodium filled.

Ferrea & Manley are brand names, not any alloy type of metal. Inconel is an alloy of stainless steel, fairly exotic {the X-15 was made with huge quantities of parts out of inconel}, are you sure you can find exhaust valves for a 930 made out of it?

Valve seats are never copper, always hardened steel, some times they can be found made from an alloy called Stellite, and on newer cars even ceramic.

Bronze guides are pretty standard fare.

Mark

[turbo nut]

They do make seats out of Beryllium copper. we have used it several times.

[full quack]

Good to know!

However Beryllium copper is a far cry for plain old copper... don't-cha-be-know'n. Plus you must be very carefull to have complete proper ventilation when machining Beryllium copper, as the off gas fumes are extremely hazardous to your health. I've machined lots of this in the past.

Mark