Lister's:
Those of you who know me know that I've come up with some real
hair brained ideas at times. Well this question may be another one of those way
out ideas. Y'all be the judges. A couple of months ago I was working on a
"blown" 496 Hemi for a friend (by the way, this is not in a TR, it's in a "70
Superbird). I am of the opinion that engines are pretty much the same, at least
in principle. Well, come to find out this has what they call roller cams and
lifters. Not rockers mind you. The lifter has a set of roller bearings in the
surface which contacts the cam lobe. The cam lobe is ground with the same
amount of lift as a normal cam for this car, but the ramp to fully open is
extremely steep and the open duration is very long. The roller bearings are
there to handle the extreme loads placed on the lifter by the steepness of the
lobe.
The idea with it is to decrease the amount of time the valve is
moving between closed and open, and leave it fully open longer. Sounds like a
great idea to me! There are other considerations to take into account. With
this setup they don't want the lifters to rotate for obvious reasons, so they
place a pivoting bar between every two lifters to stop this. Kinda hard to
describe without a picture, but a needed evil that I think could be substituted
by something else.
Anyway, my question is; has anyone ever seen this setup before?
Tried it on one of our TRactor motors before? Think I'm crazy? (don't all raise
your hands). It just strikes me in my idle time that we send piles of money for
roller rockers which look cool but gain us very little h.p., while roller
lifters may gain more. By the way, I'm told this is twenty year old technology.
My friend is suppose to give me a used roller lifter to play with so I'm
interested in your ideas. Thanks - Ed
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