it takes two revolutions
??????
As I said before, it takes two full revolutions of the crankshaft to go through the firing order. There is an obvious difference between the compression stroke and exhaust stroke  even though both go to TDC position on every rotation. If you start with number one on compression  the second cylinder in the firing order will come up in 90° and so on  there will be a second piston at TDC in every case  but adjusting the closed intake valve on it risks being off the base circle. Every 90° the cam closes both valves on a cylinder  that's the one you want.
The micrometer effect of the rocker nut 
A 3/824 UNF nut moves the pivot down .042 per turn ÷ 6 flats = .007 per flat. For a 1.5:1 rocker this means that three flats (180°) will compress the lifter plunger 3 x .007 x 2.5 ÷ 1.5 = .035". If you turn it 6 flats (360°) its doubled to .070".
For a 1.6:1 rocker  the math is 3 x .007 x 2.6 ÷ 1.6 = .034" (in 180°)
