Without overly complicating it,I was starting to do this and laid out firing order 392 vs crank degrees. 413 the same firing order , but distributor turns CCW other is CW . My new damper marked every 90 degrees.
392 and A block;( B may be in the same situation, but not there today). Starting with #1, at TDC firing (which position by the way is 360 of crank rotation AWAY (forward CW) from where you align timing chain dot marks..(=confusing as hell , I have ever seen that fact talked about) . Yes , The piston is on TDC when chain marks are aligned ( at install ) , cam key points at about 4 o clock but that is not the compression or firing stroke. On firing stroke on #1 , the dot on cam sprocket is at top (180 more on cam--SO, on next full rotation of engine ---and firing , yes pointer is back at TDC----.and cam has turned one half turn. #1 Piston went down and came back up. Fire!
So, I started overthinking again. ---- on a V8 , 4 firing TDC's happen per turn of crank, 360/4 = every 90 degrees. So, measured degrees from the #1 firing TDC . 1,8,4,3. =0, 90, 180, 270 ; 360 position (start of next turn) is the start of 6,5,7,2 firing ,and yes #1 is at TDC again at 360 but not firing ; 360,450,540,630. So 720 is 0 again ,same as # 1 firing . 720 Crank degrees. that is = 360 distributor and cam degrees , rotor is back pointing at 1. = 18436572
Now all through Mopar land is some kind of chart ( I have a copy) saying adjust I 2 and E 8 when # 1 is at TDC on compression / firing stroke , = still requiring 8 bumps of crank by 90 each , to do 16 valves . I do not get this advice from on high at all. If #1 is firing on TDC by definition both valves are closed, that is when to adjust #1 valves ? Especially if moving it 8 times anyway. There is probably some pattern where one could move only 4 times, and adjust say 4 at once, why this line of inquiry started in the first place (from me). But instead sometimes 40 posts in an online sequence with guys killing each other over how to do this, but none of them advocate what I just said. They confuse themselves with the base circle and " heel" (??) of cam etc . Tangled in underwear? Base circle is a long time % duration of cam, certainly where both lifters are sitting when cylinder fires?
Wha???? is my reaction. Anyone with me? Thoughts?? "for those who do not understand, no explanation suffices" is my reaction to all this, but maybe I am missing something important!???? If so, not alone..
Best, John G
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