I put a summit racing camshaft part # SUM-1103 in a 400sb with 3 way adjustable timing gears set at 0. When starting it, it is difficult and seems like the timing is off. Vacuum is at 15 inHm, but my timing mark is at the top of the balancer and it will stall if try adjust it to the gauge. Checked the distributer timing 4 or 5 times and if moved 1 tooth either way it runs worse. I have 2 options left in adjustment on the gears, I can set it on "A" which advances the cam 2 degrees or "R" which retards it 2 degrees. Question is, without using a degree wheel, which way should I go?