I built a 327 in 68 with a roller cam. They were really hot then.
-----Original Message-----
From: owner-fot@autox.team.net [mailto:owner-fot@autox.team.net] On Behalf
Of EDWARD BARNARD
Sent: Friday, August 13, 2004 4:45 PM
To: fot@autox.team.net
Subject: Engine question
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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