The discussion on lifters is of interest to me. I?d like to see some
independent verification of the recent statement regarding lifter bore being
at some angle relative to the cam bore.
What I believe is the bores are perpendicular to the cam bore but offset from
lobe centerline to facilitate lifter rotation. I recently did some research on
cams and lifters for the wet sleeve engines and have concluded that factory
stock cams and lifters are ground flat and lifter bores are offset to
facilitate lifter rotation. My bases for the conclusion is via verification at
a cam grinder that the stock lobes (and my Kastner D cam) are ground flat by
installing several OE cams between centers in the cam grinders equipment and
sweeping a dial indicator across the lobes and the heals which verified dead
flat grind.
With regard to lifters I took several used but known to be OE lifters that were
in good shape and placed them end to end, there was no rocking and they mated
as though they were lapped together. I did the same with new lifters from a
well know supplier and placed them end to end and they rocked showing a slight
radius. These radiused lifters combined with a flat cam are not matched for
lifter rotation and can lead to rapid cam and lifter wear. If using a cam that
has a taper ground lobe with the radiused lifters you will get rotation.
I have no idea what effect on wear an offset lifter bore has with a tapered
lobe cam and radiused lifter. Maybe someone else can comment on that.
Perhaps this is old news to many racers but I suspect that some engines have
been built with mismatched cams and lifters that led to rapid cam and lifter
wear which was wrongly blamed on oil and break-in procedures.
JVV
From: Mike Harmuth via Fot
Sent: Thursday, November 16, 2017 8:47 AM
To: FoTTriumph
Subject: Re: [Fot] Peugot lifters 504
"And they've been used in at least one 1296 Spitfire engine, where they're much
larger in diameter than stock."
Now you have my interest, I have a small block 1296 block with worn lifter
bores and my engine builder couldn't find a slightly larger lifter. I'm
guessing he didn't look at a Peugeot parts catalog. Does anyone have a lifter
part number or a spec so I can investigate bringing this block back from the
dead? It was mentioned that the TR bores holes are not parallel to the block,
are the small journal 1296 bore the same?
thanks
mike h
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