My new Isky solid flat tappit cam (video)

You timing by ear, least thats how I been doing it. Once the advance is fully in-around 3,000 rpm- you keep advancing the timing by turning the dist until the engine speed stops increasing and lock it down. I then use a timing light to just see where its at and then road test and make small adjustments from that setting.

How do you time by plugs, doesn't the A/F change the plug colors