I have always installed my solid cams a couple degrees advanced with great results. My new short block came with a roller cam by CamMotion, I called CamMotion and he said my 705/661 281/283 cam is on a 104, he had me degree it in at 106 as he thought 104 with my 500" 440-1 headed combo would be all bottom end and less top end so I put it in at 106, especially since I'm running a true 10.5" tire. We'll see how it goes.