The POH does list a speed for best glide however that was based on the stock prop a 76" Hartzell, I got a FAA field approval to install a 198cm 3 blade MT prop (that is 20 lbs lighter), the effect on approach when moved to full fine for landing is like throwing a chute out the back. The reason for the original question is I'm trying to get some off my glide capability back if I have an engine failure as this new props air braking effect is significant.