Nothing wrong with your timing compromise, IMO. Another thing you could try is a 1" 4 hole spacer on top of that manifold. It could clean up the low end/idle a little for cheap. It did on my tunnel ram, anyway. There have been many apples to apples tests that don't support all the hype about single plane manifolds being so terrible on the bottom end/mid range. Besides, for having your fun, it's an easy give away for how hard it pulls from about 3,500 to 6,500. And that's another reason to keep the total advance at 38 or so as, from my own experience, a couple of brews and some good dirt make the foot heavy and the ears deaf.