Been out of the hobby for 6 1/2 years. When did they quit making mac 67's? Do they still make parts? I've seen new cmb 67 HR's, is that the only current new 67 made now?
I'm sport running with 20% and after 4 tanks of fuel (from break-in) I blew both plugs when I finally went to WOT on my cmb cam 67.Bud T-5. Using a x450/3. Going to try a 447/3. I've since switched over to single plug head. What pipe length should I try w/ 20% and 447/3? How much fuel do I need...