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Rex_A_Lott · 03-21-2012, 10:04 AM

I’ve been following this post for a couple of days and it was interesting to me for a couple of reasons: One being I just bought a cam from Jim Brierley, and he warned me about buying the too small lifters. Another reminded of something I’d read, but I couldn’t remember the numbers, so I had to go back and look it up…
This was in a book about SBC valve trains, and they were comparing the stock lifter diameter (.842) and the allowable rate of lift ( .007 in/deg) with that of the SBF, ( .875 and .00755 in/deg). I did a little cross multiplying and interpolated these numbers out to be .009707 in/deg for a 1.125 lifter and .0102 for the 1.1875 lifter. Is this reasonable or did I do the math wrong? Or can you even compare a rocker arm setup to a direct acting lifter?
If frugal Mr. Ford thought it was important enough to change his pushrods, I just wonder why nobody is doing it today? I realize the market would be small, but I would think that anybody wanting a new or reground cam would want the correct size, adjustable lifter.
Maybe its just not worth the difference, or maybe Mr. Stipe and Mr. Brierley ( and others) would just rather use a little less aggressive lobe and not run the risk of increased wear and noise.
One more question, are the lifters convex to promote sliding/rotation, and are they hardened/ chilled iron? Just curious if you could turn a set in a lathe that would last or if any home made attempts like this would disintegrate…
Thanks for anybody’s thoughts…just trying to learn a little here.Looking forward to hear what the pros have tp say.

03-21-2012, 10:04 AM	#18
Rex_A_Lott Senior Member Join Date: Jun 2011 Location: Upstate South Carolina Posts: 794	Re: Model B adjustable Lifters ? I’ve been following this post for a couple of days and it was interesting to me for a couple of reasons: One being I just bought a cam from Jim Brierley, and he warned me about buying the too small lifters. Another reminded of something I’d read, but I couldn’t remember the numbers, so I had to go back and look it up… This was in a book about SBC valve trains, and they were comparing the stock lifter diameter (.842) and the allowable rate of lift ( .007 in/deg) with that of the SBF, ( .875 and .00755 in/deg). I did a little cross multiplying and interpolated these numbers out to be .009707 in/deg for a 1.125 lifter and .0102 for the 1.1875 lifter. Is this reasonable or did I do the math wrong? Or can you even compare a rocker arm setup to a direct acting lifter? If frugal Mr. Ford thought it was important enough to change his pushrods, I just wonder why nobody is doing it today? I realize the market would be small, but I would think that anybody wanting a new or reground cam would want the correct size, adjustable lifter. Maybe its just not worth the difference, or maybe Mr. Stipe and Mr. Brierley ( and others) would just rather use a little less aggressive lobe and not run the risk of increased wear and noise. One more question, are the lifters convex to promote sliding/rotation, and are they hardened/ chilled iron? Just curious if you could turn a set in a lathe that would last or if any home made attempts like this would disintegrate… Thanks for anybody’s thoughts…just trying to learn a little here.Looking forward to hear what the pros have tp say.