so i was reading in this this copy of HOT RODDING THE BUICK by Bob Russo about the things Max Balchowsky use to do to his nailheads he would run in his race cars. the part the struck me as odd, was when it said that he would chrome plate the valve stems for better lubrication. it was suppose to reduce friction between the stem and the guide and elliminate wear practically. it was around .0002 of an inch of chrome plating that was applied. my questions are; has anyone else ever heard of this or done this? does it really work? is it neccesary on newer style valves? i'm kinda new to the whole engine performance tricks thing, so this could be an entirely rookie type question.
Pretty much all quality replacement valves for the past 30 years have a flash chrome plating on the stems for wear resistance.
Chrome plated stems allow for tight valve guide clearances without excessive stem and guide wear. Chrome plated stems and tight stem clearances are used with "self-lubricating" phosphor-bronze guides or K-line guide liners with teflon valve stem seals. Very little or no oil at all gets past those type seals and the tight clearances. I set my valves up with .0015" - .002" (I) and .0025" - .003" (E) stem clearances. Tight stem clearances will provide accurate valve seating, better oil control and better intake and exhaust port flow. Some automakers prior to the Clean Air Act Extension in 1970 had .0025" - .003" (I) and .003"- ,0038" (E) clearances. I suppose that was because the factory did not install bronze guides that would permit tighter clearances. A noticable puff of blue smoke would be seen when starting the engine on new cars and the EPA did not like it.
Its called industrial hard chrome plating and its been around forever .great for wear resistance on things like Hydraulic rams,cylinder liners,crank journals and most anything that rubs and wears.used in plastic molds so parts come away freely .great for recllaiming worn out parts .say a crank is galled on one journal , it is ground to clean up ,then ,once wax coated a section around the journal is laid bare .it is plated at 2amps per sq inch at a depost rate of one thou per hour .then finish ground back to std
The Jalopy Journal
