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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