Old valve catalogue

[Bob Culver]

A colleague recently acquired a 1935 Austin 10. The motor has been recon but not run. As is more or less usual many aspects of the work are dubious. 
The inlet valves are well used James XB 1077, possibly former exhausts.
The brand new exhausts with exactly same size stem bear only the number 5017.
Has anyone an old valve catalogue from which they can confirm that these are in fact exhaust valves (of at least XB steel) please?

[Stuart Giles]

On the internet: the spec of XB steel.  Metallurgy should have moved on from this standard. Its SAE equivalent dates from the 1950s
https://www.carpentertechnology.com/en/p...lve-steel/

[Bob Culver]

Thanks Stuart

It was the common exh valve steel until about 1960. Has the merit of moderate expansion and hard stems. Cars so equipped required regular valve grinds and burned valves were common. Ritual almost unknown since. XB is magnetic. I dunno when XB originated but replacement exh valves for Sevens were often of lesser steels. (ie James VK+). Throughout use by my father and self, with pre XB valves my Seven needed a valve grind about 5000 miles. Other early hard users of Sevens report the same.
Presumably valves are now modern non magnetic material. I dunno what life is obtained in Sevens but remarkably superior. I found with Javelin cars XB valves short lived on weak mixtures, but modern valves unmarked, even with cracked valve seats.