Valve Guides: Which to buy?

Much as I like the drag racing threads...gotta bring up a tech question.

There are two types of valve guides that are listed in PP catalog, bronze-silicon and phosphorus. OEM and domestic, respectively. What are the differences and the recommended solution?????

Thanks,
-d

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Dave
1972 911T (E motor) RSR replica project
http://members.nbci.com/dtwinters/garage/

I once saw something in the Readers Letters section in an old issue of Excellence (1995 I think) where someone asked about valve guides. Bruce Anderson wrote back that he should get the phosphorous bronze ones.

Can't remember the details, sorry. Anyway I hope this helps you a bit.