Can't say I've had a no wind situation, but at the top of the green arcs, at 23MP, 2350rpm, Id guess 140mph. Thats on a G model, no mods other than wheel pants.
I just flew mt 1982 T182R Turbo yesterday here in So Cal. At 6'500 feet MSL at about 75% power I was seeing about 120KTS IAS. When I pushed the manifold pressure to just under red line I was able to get about 132kts IAS. If you make sure you have a clean airplane, close the cowl flaps, lean properly, adjust prop RPM and fly about 10,000 feet MSL a Turbo like mine should have no problem with 140KTS IAS. Also, make sure your rudder trim is adjusted too because different speeds affect the trim needed to keep your airplane tracking true without any unintentional yaw. Also seems to me that airspeed is easier to maintain once you get there. For instance, nose the plane over just a bit to reach a higher airspeed and level off slowly while increasing power and checking that you have a clean airplane and you should be able to pick up a few extra knots and maintain them. I know that my last piece of advise goes against the laws of physics a bit, but just try it and see if it works for you.
My t182t @ 7-10000ft, 75% power will produce 139-143 TAS.
On any 182 flying under max gross, you can pick up a few knots by placing any baggage or cargo as far aft as possible. The aft CG reduces the down force requirement of the elevator, reducing drag.
I measured my speeds for comparison. 1975 C182P, stock engine, STOL with flap gap seals, micro VG's, stock wheel pants and all normal fairings in place, cowl flaps closed, and leaned to 100 F rich of peak with single probe digital EGT. TAS Speeds confirmed by GPS ground speed. full (equal) tanks, 350 lbs of two persons and baggage (persons 300 lbs, with 50 lbs of baggage loaded into rear most station). I recently had my mechanic adjust aelerones and flaps (hopefully) to proper rigging.
Book TAS (xxx mph) followed by my measured TAS (xxx mph) and flight conditions.
Book TAS (157 mph) my TAS (145 mph):
2500', 60F oat, 30.34", 2300 rpm/23"mp
Book TAS (159 mph) my TAS (147 mph):
9600', 45F oat, 30.34", 2450 rpm/19"mp
Book TAS (154 mph) my TAS (144 mph);
10,500', 45F oat, 30.32", 2300 rpm/19"mp
I realize my atmospheric conditions aren't exactly standard, but I was also was about 900 lbs lighter then the book-chart too.
I don't know why my TAS aren't closer to book TAS. Wish I could get there! I have found that even small differences in L/R fuel will make the plane loose several mph due to the resulting uncoordinated flight condition.
Those in the know...how do we get to book speeds????? I think mine is properly rigged...?
