I fly a Turbo 182 and was told to decrease my manifold pressure 2" at a time every 2 minutes or so to keep from shock cooling the engine. In my IFR training so far, I am told I need to keep my speeds up until the FAF. How do I reduce the manifold pressure slowly to avoid this while complying with my CFII's request to keep my speed up? Also I have had a couple approaches where the FAF to the runway seems so close and by the time I slow down, put in flaps and establish the 90 Knots, I am way to high and super close to the runway. Seems to me like I should be able to start setting up for the approach speed at the IAF.