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Old 07-13-2020, 02:49 PM   #18
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Join Date: May 2010
Location: Long Island, NY
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Default Re: Off shore adjustable lifters

Originally Posted by 19Fordy View Post
GOESFAST, Thanks so much for taking the time and effort to answer my question. I feel better now, knowing Topline is an excellent replacement.

I don't remember if the original "Johnsons" were flat or did they have a slight crown.
Are the Topline lifters flat or crowned? I do still have an old set of Johnsons lifters that are ground with a slight radius. Is that good, bad or desirable only with certain cams?

Thanks, Jim in FL
They've always had the "crown" on the lifter face, it helps with two things, first, it helps to keep the lifters "spinning" for a constant oil supply and second, it helps keep the cam running into the unit. Sort of "threading" it into the block!

They also have the a radius on the adjusting nuts as well where they contact the valve stem. This is most likely done to keep the point-of-contact between the stems and the adjusting nuts to a minimum, makes it less important where "alignment" would be an issue??

Thanks, Gary in N.Y.

P.S. On side note almost all cam lobes are ground with a taper to correspond with the lifter radius! Again, this keeps everything "spinning" so to speak! The only lifters (I believe) without a radius were used on the old "Nailheads"?? One of the cam guys up here may know for sure? This photo from Isky's catalog may help understand what's occurring?
Attached Images
File Type: jpg Isky Cam Pattern.jpg (131.1 KB, 545 views)
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