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Degree Of Full Lift For My Cam?


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#1 hughzy69

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Posted 05 June 2012 - 08:09 PM

hi guys just wondering if anyone knows the degree of full lift for my cam? its a kent vp3c cam.

cheers tom.

#2 hughzy69

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Posted 05 June 2012 - 08:16 PM

is it 106 degrees?

#3 bmcecosse

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Posted 05 June 2012 - 08:19 PM

It's a bit like the excellent old 544 cam, but for some reason with less inlet duration.... and quite a lot of overlap, so probably not great for emissions.. Why does the max lift matter to you? I believe it is at 106 degrees.

Edited by bmcecosse, 05 June 2012 - 08:21 PM.


#4 hughzy69

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Posted 05 June 2012 - 08:21 PM

so i achieve said lift?

#5 bmcecosse

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Posted 05 June 2012 - 09:06 PM

You will be bound to get the lift! It's not a cam I would use - the 544 is superb....

Edited by bmcecosse, 05 June 2012 - 09:07 PM.


#6 dklawson

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Posted 05 June 2012 - 09:28 PM

For a symmetric cam profile the max lift occurs at the lobe center angle or LCA. You will want to know the LCA so you can dial it in with vernier sprockets or offset keys in preference to the dot-to-dot method of cam timing.

Have you degreed a cam before?

#7 bmcecosse

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Posted 05 June 2012 - 10:16 PM

If the cam has been correctly made - dot to dot is fine.......and if any doubts, it's easily checked by the 'equal lift at TDC on overlap' method........ But of course, timing it 'perfectly' like that may not give the best performance characteristics anyway.......

Edited by bmcecosse, 05 June 2012 - 10:18 PM.


#8 dklawson

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Posted 06 June 2012 - 12:29 AM

There are too many reports of cams being "out" due to machining and grinding tolerances to not check the LCA if you have the ability.

#9 ACDodd

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Posted 06 June 2012 - 04:50 PM

http://www.mlmotorsp...pic,1147.0.html

Nuff said.

AC

#10 Cooperman

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Posted 06 June 2012 - 06:43 PM

http://www.mlmotorsport.com/forum/index.php/topic,1147.0.html

Nuff said.

AC


The biggest 'dot-to-dot' error I've had was 9 degrees retarded. Cam was a 276, timing gears were 'budget' duplex. I've had several with 5 degrees error.
To get the best from an engine the cam timing really does need to be done accurately. +/- 1 degree is normally acceptable and I set 2 degrees advanced at new build to allow for initial chain stretch.




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