Rotary valve timing

[brucep1bruce]

Can l put the degree wheel at 0 on the top of the intake port and measure down 64 degrees mark it and install the top of the rotary valve to time it at the 64 degree mark? It's a lot easier to see that way as opposed to using a mirror or removing the exhaust. Especially if your old and fat like me.

 

[brucep1bruce]

On a 787 motor

 

[mikidymac]

No, the bottom of the rotary valve window would line up with the 64 degree mark from the top of the intake port, the top would be at 147 degrees from the bottom of the intake port so that the MAG port is open when the MAG piston is at TDC.