[Fot] Do(o)med or flat lifters?

Larry Young cartravel at pobox.com
Fri Aug 31 09:17:24 MDT 2018 

Greg,
Thanks for posting this. I have seen the same thing in "virgin" engines, 
but have not taken so many apart. I was hoping you or Glen or someone 
with more experience would chime in.
- Larry

On 8/30/2018 1:20 PM, Gregmogdoc--- via Fot wrote:
> I bought my 1964 Morgan +4 new in 1965. When I first
> took the engine apart to modify it for more power at
> around 16,000 miles, there were two lifters in the
> engine that were not rotating!  They had "butterfly"
> wear patterns on the bottom of the lifters caused by
> the lifter oscillating back and forth. So this is a
> fault in the original production of the engine.
> Over the years, whenever I have taken apart what I
> believe to have been "virgin" engines, I have ALWAYS
> come across 2 or 3 lifters in each engine that have
> not been rotating.  When they don't rotate, they
> eventually pit and fail, then damage the camshaft.
> The original cam lobes were flat, not tapered, and
> relied on the offset of the tappet bores in the block
> from the center of the cam lobes to induce rotation.
> It was not enough!  All or our cams are ground with a
> taper to the lobes that matches the offset of the
> lifter bores in the block to the cam lobes. This
> means that 4 lobes have a taper in one direction and
> 4 lobes are tapered in the other direction. The
> tappets are ground with a crown to match. Since we
> have been doing that, all the lifters rotate
> consistently, and if the lifters are hard enough, we
> do not have excessive wear problems unless poor
> quality oil is used or the break in procedures and
> not correctly followed.
>
>
> Greg Solow
> The Engine Room
> Sports Car Specialists
> Santa Cruz, CA 95060
> 831 429-1800
>
>
>
> ------- Original Message -------
>  From    : fubog1 via Fot[mailto:fot at autox.team.net]
> Sent    : 8/29/2018 4:08:02 AM
> To      : tr4racing at googlemail.com;
> pegandbobm at aol.com; rkrantz77 at comcast.net;
> fot at autox.team.net
> Cc      :
> Subject : RE: Re: [Fot] Do(o)med or flat lifters?
>
>   
>   #1 cause of failure- dirt 40+%.
>
> #2 cause of failure- assembly error 40+% (note
> assemblers responsibility to ensure parts are to spec)
>
>
>
>
>
>
>
> This is part of the problem with rebuilt failures, it
> isn't all "defective parts".
>
> HTH
>
> Glen
>
>
>
> problems came in when people used aftermarket parts
> or tuning parts.
>
>   
>
>
>
>   
>
>
>
>   
>
>
>
> -----Original Message-----
>
> From: Chris Marx via Fot <fot at autox.team.net>
>
> To: tr4racing <tr4racing at googlemail.com>; pegandbobm
> <pegandbobm at aol.com>; rkrantz77
> <rkrantz77 at comcast.net>; fot <fot at autox.team.net>;
> Fubog1 <Fubog1 at aol.com>
>
> Sent: Wed, Aug 29, 2018 5:37 am
>
> Subject: Re: [Fot] Do(o)med or flat lifters?
>
>
>
>
>
>
> #AOLMsgPart_1.2_51b0e82b-6923-4884-aaee-ebe3d9794a06
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>
> Let me add:
>
> Standard means….from factory
>
> Tuning means…..from so called “experts”
>
> I don’t know how much experts they are but one thing
> is obvious.
>
> In the past, Triumph seems not to have much trouble
> with camshafts…..problems came in when people used
> aftermarket parts or tuning parts.
>
> This is always suspicious to me.
>
>   
>
> Cheers
>
> Chris
>
>   
>
>
>
> Von: tr4racing at googlemail.com <tr4racing at googlemail.com>
>
> Gesendet: Mittwoch, 25. Juli 2018 07:54
>
> An: pegandbobm at aol.com; rkrantz77 at comcast.net;
> fot at autox.team.net; Fubog1 at aol.com;
> tr4racing at googlemail.com
>
> Betreff: AW: [Fot] Do(o)med or flat lifters?
>
>
>
>   
>
> I had a look around German forums and it seems to be
> a difference between tuning and standard engines.
>
> Standard – flat
>
> Tuning – domed.
>
>   
>
>   
>
>   
>
> Von: pegandbobm at aol.com <pegandbobm at aol.com>
>
> Gesendet: Montag, 23. Juli 2018 22:17
>
> An: rkrantz77 at comcast.net; fot at autox.team.net;
> Fubog1 at aol.com; tr4racing at googlemail.com
>
> Betreff: Re: [Fot] Do(o)med or flat lifters?
>
>   
>
> Not an expert but I WILL GUARANTEE the lifters in my
> air cooled German made VW Formula Vee engine have a
> slight radius/angle.  I check this before each
> rebuild to ensure they have not flatten.   Pre-Trump
> I think Germany was still considered part of Europe>
>
>
>   Bob
>
>
> -----Original Message-----
>
> From: Ron KRANTZ via Fot <fot at autox.team.net>
>
> To: Christian Marx via Fot <fot at autox.team.net>;
> Fubog1 at aol. com <Fubog1 at aol.com>; Christian Marx
> <tr4racing at googlemail.com>
>
> Sent: Mon, Jul 23, 2018 1:46 pm
>
> Subject: Re: [Fot] Do(o)med or flat lifters?
>
>
>
>
> The reason for a slight angel on the lifter is to
> keep it from digging into the ramp on the cam lobe
> due to an aggressive acceleration design.  Typical
> American (cannot say what European mfg. does) lifters
> have approximately a 60 inch radius.  I even have an
> additional edge radius put on the lifters.  The cam
> lobes have a slight taper side to side for rotating
> the lifter.  Lift on a cam is limited by base circle
> radius which in turn is limited by cam bearing
> diameter.  Then you get into duration and how fast
> you can get the valve open.  All the Triumph "flat"
> tappets I have ever seen have a slight radius.  The
> rules say you must retain the same type (flat,
> roller, mushroom) lifter as stock.  My question is
> "how flat is flat".  Rule does not say the lifter has
> to rotate.  If a lifter has a 0.75 inch radius across
> the lifter diameter and no taper on the cam lobe,you
> can keep the lifter from rotating and accelerate the
> cam opening very fast.  Think about that.
>
>
> On July 23, 2018 at 8:46 AM Christian Marx via Fot
> <fot at autox.team.net> wrote:
>
>
> This may be true for American engines.
>
>
>   
>
>
>
> All European engines have no angel in the Cam shaft.
> And all the tappets, lifters, rollers, are flat. Dead
> flat. No light with an edge on it.
>
>
>
>   
>
>
>
> So maybe this is just an American thing?
>
>
>
>   
>
>
>
>   
>
>
>
> Cheers Chris
>
>
>
>   
>
>
>
> fubog1 < fubog1 at aol.com> schrieb am Mo., 23. Juli
> 2018, 15:40:
>
>
>
> This is well covered in many engine-building books &
> I've discussed it at length with several camshaft
> engineers over the years.
>
>
>
> It's my understanding that the lobe should have a
> very slight angle ground in, and the "flat" tappet
> really isn't, it's very slightly convex.
>
>
>
> This will give it rotation, if it doesn't rotate it
> will wear.
>
>
>
> There could also be spring pressure or lubrication
> issues?
>
>
>
> In any case I would discuss it with the tappet
> supplier before doing anything, at the least make
> sure that they are sufficiently hard to begin with
> and can be reground.
>
>
>
>   
>
>
>
> Glen
>
>
>
>   
>
>
>
>   
>
>
>
>   
>
>
>
> -----Original Message-----
>
> From: Christian Marx via Fot < fot at autox.team.net>
>
> To: fot at autox. team. net < fot at autox.team.net>
>
> Sent: Mon, Jul 23, 2018 6:04 am
>
> Subject: [Fot] Do(o)med or flat lifters?
>
>
>
> In the past we had this discussion.
>
>
> I've bought some high quality lifters from USA, made
> from tool steel I suppose. 400$ they've cost..... and
> started to fail. On 3 of them, the very center does
> show e few pittings. Also visible that only a small
> part of the Cam is used.. The cam is okay
>
>
>
>   
>
>
>
>   
>
>
>
> The machine shop will grind the lifters dead flat, as
> they should be, they say.
>
>
>
>   
>
>
>
> Cheers
>
>
>
> Chris
>
>
>
>
>   
>
>
> Am 18.07.2018 02:12 schrieb "fubog1 via Fot" <
> fot at autox.team.net>:
>
>
> Yes, lacking access to a Cam Doc, you can use a set
> of V or bearing blocks, a degree wheel, dial
> indicator, and a bit of time, checked at 5 cam
> degrees, works fine.
>
>
>
> I'm still old school though, I plot them out on graph
> paper!
>
>
>
> That will give you the lobe profile but most folks
> don't have the full specs on the cam, usually just
> advertised lift and duration.
>
>
>
> Since the tip of the lobe usually starts to go away
> first, a simple lift measurement will reveal the
> worst, best done with a dial indicator cuz some
> (cheap) cams are ground on different base circles.
>
>
>
> Generally, ramp wear is unusual if the tip is still
> OK, although there can be exceptions.
>
>
>
>   
>
>
>
> Glen.
>
>
>
>   
>
>
>
>   
>
>
>
>   
>
>
>
>   
>
>
>
> -----Original Message-----
>
> From: timmmurphh < timmmurphh at gmail.com>
>
> To: 'fubog1' < fubog1 at aol.com>; rbtr3a < rbtr3a at cox.net>
>
> Sent: Tue, Jul 17, 2018 12:38 pm
>
> Subject: RE: [Fot] Cams
>
>
>
>
>
> By degreeing the cam using increments of 10
> crankshaft degrees (5 camshaft degrees) and then
> plotting the results in Excel, it is possible to get
> a very accurate picture of the profile of the cam.
>
>
>
>   
>
>
>
> I’ve attached a spreadsheet showing an intake and
> exhaust lobe comparison two years apart of our
> Kastner G3 cam for reference.
>
>
>
>   
>
>
>
> Tim Murphy
>
>
>
> #317 TR4
>
>
>
>   
>
>
>
> From: Fot <fot- bounces at autox.team.net> On Behalf Of
> fubog1 via Fot
>
> Sent: Monday, July 16, 2018 6:31 AM
>
> To: rbtr3a at cox.net; fot at autox.team.net
>
> Subject: Re: [Fot] Cams
>
>
>
>   
>
>
>
>
> Generally any obvious wear or pitting would make it
> unserviceable, but the wear isn't always so obvious.
>
>
>
>
>
> You can measure the lift and compare to spec, that
> will show any worn lobes, but the best way is to find
> someone who has a "cam doctor". It's a machine that
> sets it up and measures the complete profile.
>
>
>
>
>
> Usually if there is anything apparent that suggests
> that there may be problems, there are...
>
>
>
>
>
>   
>
>
>
>
>
> Glen
>
>
>
>
>
>   
>
>
>
>
>
>   
>
>
>
>
>
> -----Original Message-----
>
> From: rbtr3a--- via Fot <fot at autox.team.net>
>
> To: fot <fot at autox.team.net>
>
> Sent: Sun, Jul 15, 2018 6:47 pm
>
> Subject: [Fot] Cams
>
>
>
> How do I determine if a cam is good or bad. If there
> are any marks on it does that make it bad. I do know
> that two of the lifters has pitting on the surface.
>
>
>
> Ronnie
>
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