Tight lash camshaft questions

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CamKing
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Re: Tight lash camshaft questions

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Stan Weiss wrote: Thu Sep 12, 2019 3:01 pm I knew someone years ago that happened to. Luckily his was water cooled and he was able to run some hot water into it and was off and running agai
I designed a cam for a Daytona Prototype car, over a decade ago.
The rules limited the gross valve lift and duration at .050", so I designed a cam with a .007" lash ramp.
The owner hated it, because with the aluminum block and heads, they had to preheat the engine, to get enough lash to close the valves.
Lucky for me, they won the 24 hours of Daytona, so the owner got over the lash issue.
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David Redszus
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Re: Tight lash camshaft questions

Post by David Redszus »

CamKing wrote: Thu Sep 12, 2019 12:48 pm
David Redszus wrote: Thu Sep 12, 2019 12:22 pm A ramp height of .020" over 40 deg would produce a slope of 2 deg/.001". That is to say a change in lash of .001" would result in a duration change of 2 deg.
Actually, it would change 4 degrees, because you would be changing each side 2 degrees.
Thanks Mike, you are correct. I should have said 2 deg per side; I was thinking event location change not total duration.
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