i run the pump on my 2 OS-160 because i run all my tanks on the CG so that as the fuel runs out my CG says the same. This sometimes puts my tank in the range of 8 to 12 inches from the carb. I love the fact that i have constant fuel pressure. That OS-160 is a beast if you get those needles correct. That low end is the key as i stated in eariler post.....