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Hi I know buy changing from 1.5 to1.6 rocker ratio gives you more lift , But does it also make the duration figures of that cam bigger. So if at 1.5 ratio you had 246 degrees at 50 . What do you have with a1.6 ratio ? Any help much appreciated
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im pretty sute it stays the same, your lift at 50 thou then times it by your rocker ration which gives you the lift on the valve. your duration is how long your vlaves stay open for during that cycle which is determined by your lobe shape. |
Havent you learnt anything from that guy that gives sermons at church?...Captain whats his name. |
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Im going of the top of my head its been 8 years since i did this at college for my fitter apprentiship. |
Havent you learnt anything from that guy that gives sermons at church?...Captain whats his name. |
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by going to 1.6 from 1.5, the lift @ 50 will be earlier, and close@ 50 thou will be later.
i.e. longer total duration + larger total area under curve
Cam specs are usually quoted using either 1.5 or 1.6 or 1.7 or whatever.
A1 Bogan. |
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Duration is at valve lift, rather than pushrod. Pushrods will move the same, but valves will move (1.6/1.5) or 1.067 times more. So your 246 at 50 thou with 1.5 becomes 262.4 at 50 thou with 1.6.
Your maximum lift has a similar multiplier, so that is |
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whats the diferant between advertised duration and gross duration?
Is advertised were they measure the valves open time in degrees to the crank rotation after the lifter has moved the valve 50 thou and then 50 though before it shuts, add those 2 numbers |
Havent you learnt anything from that guy that gives sermons at church?...Captain whats his name. |
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Rank: Member
Groups: Registered
Joined: 18/10/2007(UTC)
Posts: 897
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whats the diferant between advertised duration and gross duration?
Is advertised were they measure the valve's open time in degrees to the crank rotation after the lifter has moved the valve 50 thou and then 50 though before it shuts, add those 2 numbers |
Havent you learnt anything from that guy that gives sermons at church?...Captain whats his name. |
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i read in a chevy forum that 1.5 to 1.6 ratio gives 6deg more duration
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