What grade of phosphor bronze is best to use?
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good question
i just use KLine's Phosphor/Bronze alloy
and sometimes use solid guides from Brodix
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And when you say tight clearance, how tight?
Scary tight

seriously, what made me start using Phosphor/Bronze alloy guides was all the problems with silicone/bronze/aluminum alloy guides ...Larry Tores who makes shaft mounted rockers (T & D) sent a Buick V6 to us to run Buick V6 in Comp Emiminator in 1980's ...when i disassembled the Dart/Buick alum V6 heads they had Phosphor/Bronze alloy guides ...i had to take a plastic hammer and knock all the valves out of the guides ..thats how tight they were...and thats after Tores Dyno tested engine and ran engine in his Opel.
This was 9000+ RPM engine ..after seeing how tight guides
could be fitted with this alloy type...i installed Phosphor/Bronze alloy guides from that day
when you fit guides that tight, your valve job has to be dead on center...give valves a little extra clearance if you think you can't get perfectly centered seat angles without runout.
i fit Phosphor guides with .001 on Intakes and .0015 on Exhaust..i haven't tried to fit them as tight as the heads Larry Tores did .
Larry Meaux (maxracesoftware@yahoo.com)
Meaux Racing Heads - MaxRace Software
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