Thanks Frank.
I'm afraid I've confused you a little.
The changes I was suggesting would make the correction on their own (a little second guessing on my behalf)
During correction you made one other change in the initialization, that is:
Old
advance=x.advance.value*2
New
advance=x.advance.value/1
previously you were multiplying advance by two, that is why in ...
ICAx=lsa-(advance/2)
I divided the advance by two.
thus with your additional change it is still off a little.
To know when it is bang on use these inputs and compare manual entry intake closure vs. the triple team of duration, lobe sep, and advance entries. When accurate they will yield the same dynamic compression number.
280 adv duration (crank degrees)
110 lobe seperation (CAM degrees)
4 degrees advance (crank degrees)
VS.
66 deg ABDC intake valve closure.
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(280/2)=140 duration crank degs either side of lobe centerline.
@ 106 ATDC intake centerline (110 - 4 degs advance) there remains 74 degrees left until BDC
thus 140-74= 66 crank degrees of the lobe will occur ABDC.
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When a 110 lobe sep cam is straight up (no advance or retard), the intake centerline is 110 crank degrees ATDC, the exhaust centerline is 110 crank degs BTDC.
If we advance 4 crank degrees (most typical) the lobe sep is still 110 but intake centerline becomes 106 ATDC and the exhaust centerline 114 BTDC.
(106 crank degs + 114 crank degs) /2= 110 CAM degrees. - most typical of nearly all CompCams
Lobe seperation has the distinction of being the only spec stated in "cam degrees", at least in common practice.
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