Valve train geometry
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Race Director
Joined: Apr 2000
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Valve train geometry
Saw Warren Johnson ( at least I think it was ) on a hot rod TV show and he said the roller on the rocker should be in the middle of the valve stem at maximum lift. I have always set mine up to start at one side and at maximum lift you are the same distance on the other side as where you started. Makes sense to me that way you have less side loading on the valve guide or more uniform side loading. Which way is right ?
i do as you ????
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From: Corsicana, Tx
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geometry
What you are looking for is a very minimal width pattern across the valve stem through its travel and centered as much as possible. Maybe .030 wide at the most is pretty good.The actual positioning of it is primarily determined by the accuracy of the rocker stud placement and the rocker arm itself and of course valveguide positioning. I've seen some heads that the basic dimensions of the studs and valves out of whack so far you didn't have a prayer.
Past that, the pushrod length will help get it centered up some and allow you to juggle slightly where it starts at.
Less travel across the stem is good...guides will love you for it!
JIM
Past that, the pushrod length will help get it centered up some and allow you to juggle slightly where it starts at.
Less travel across the stem is good...guides will love you for it!
JIM
