never really had this question answered so im asking again
#1
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JUNIOR BUILDER
Thread Starter
Join Date: Jan 2004
Posts: 77
never really had this question answered so im asking again
are the rocker arms and lifters on the non conventional headed engines (like big chief and big duke) just as reliable as conventional headed engines in terms of having more longevity. I read somwhere that the lifters and rockers wouldnt last very long in a marine continuous running situation and that some marine engine builders wont build an engine for marine use with anything other than conventional heads. Whats the real deal?
#2
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Join Date: Jun 2004
Location: lake luzerne n.y.
Posts: 87
Anytime you "offset" a motion that is designed to move in a straight line you decrease reliability, so the answer to your question is No, they are not as reliable as a conventional valve train . Big chief style heads that use offset lifters and rockers which create side forces on those components that increase wear.Pressure on the offset lifter pushes on the side of the lifter bore and has more pressure on one side of the roller than the other. Same goes with the rockers, but with there design it's not as bad.
#3
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Join Date: Feb 2006
Location: VA Hospital, Dallas, Tx (214 302 1924) cell-972-464-7400
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I will partially disagre with previous response, becuase of the difference in the quality of the componenets that are made to work with the heads in question, as compared to lesser quality stuff made to work on the conventional stuff.
I agree completely about the lifters though. If it is your budget have the lifter bores moved to the side when getting cut for the .904 lifters and that helps a bunch. You can oreder the Dart Race Blocks with no lifter bores in them and put them where they will line up better and use a straight non-offset lifter.
I prefer T&D Rockers, Many prefer Jesel.
Ed
I agree completely about the lifters though. If it is your budget have the lifter bores moved to the side when getting cut for the .904 lifters and that helps a bunch. You can oreder the Dart Race Blocks with no lifter bores in them and put them where they will line up better and use a straight non-offset lifter.
I prefer T&D Rockers, Many prefer Jesel.
Ed